HP would like to thank the following for their contribution:
Tony Hutchins, Wellington, NZ
Luiz Vieira, UNIPAC, Brazil
Gene Wright, Lipscomb University, USA
NOTICE
Hewlett-Packard Company makes no express or implied warranty with regard to the keystroke
procedures and program material offered or their merchantability or their fitness for any
particular purpose. The keystroke procedures and program material are made available
solely on an "as is" basis, and the entire risk as to their quality and performance is with the
user. Should the keystroke procedures or program material prove defective, the user (and not
Hewlett-Packard Company nor any other party) shall bear the entire cost of all necessary
correction and all incidental and consequential damages. Hewlett-Packard Company shall not
be liable for any incidental or consequential damages in connection with or arising out of the
furnishing, use, or performance of the keystroke procedures or program material.
This HP 12C Platinum Solutions Handbook has been designed to supplement the HP 12C
Platinum Owner's Handbook by providing a variety of applications in the financial area.
Programs and/or step-by-step keystroke procedures with corresponding examples in each
specific topic are explained. We hope that this book will serve as a reference guide to
many of your problems and will show you how to redesign our examples to fit your
specific needs.
This book expands the original HP-12C Solutions handbook with additional solutions in
algebraic mode. It contains the same RPN program keystrokes and RPN step-by-step
procedure keystrokes, in columns headed “12c platinum / 12C RPN Keystrokes”. The
alternative algebraic keystrokes are tablulated under “12c platinum ALG Keystrokes”. In
program listings the “Display” columns show the keycodes as seen on the HP 12C
Platinum.
Appendix A also contains algebraic listings for all the RPN programs given in Part III of
the HP 12C Platinum Owner’s Handbook.
Presentation of Algebraic and RPN
The conventions used to differentiate between RPN and ALG mode are:
1.
Program Listings
Complete and separate listings are given for all programs. They appear side by side
in two columns with RPN on the left and Algebraic on the right.
2.
Step-by-Step Keystroke Procedures
As for programs separate columns are used, with the RPN keystrokes on the left
and the Algebraic keystrokes on the right.
3.
Program Instructions
Program instruction steps are generally the same for both modes. Any differences
are shown by clearly framing alternative steps and annotating the step or steps in
the first frame as RPN, and those in the second as ALG.
4.
Text
Occasionally there are small differences which need to be indicated in the text
2
Introduction 3
itself and the ALG alternative is then indicated parenthetically.
5.
Usage of \(³)
To activate the ³ key it is sufficient just to press \, with the HP 12C
Platinum in ALG mode. In step-by-step and program instructions where the only
difference between the modes is that \ is used in RPN mode and ³ is used
in ALG mode, \(³) has been used to indicate both alternatives.
Using the RPN Programs on the HP-12C
Apart from GTO instructions, the keystrokes given in this book are exactly the same for
the HP 12C Platinum and the HP-12C. There are two notational differences to bear in
mind when typing the RPN programs into the HP-12C:
1.
One keycode, for F, is different.
2. Line numbers tabulated as 000 to 099 refer to lines displayed as 00 to 99 on the
HP-12C. The relevant two digit line numbers should be used when typing GTO
instructions on the HP-12C.
Notes:
1. All display columns in the examples this book show 2 decimals. This is set by
pressing f2.
All programs that do rounding, amortization or depreciation will give slightly
different answers if other than 2 decimals are showing.
2. Three of the original programs have been updated:
a. The last program in the Real Estate section (ATNCPR) now takes the capital
gains tax rate as a separate input, and an extra example has been added
showing a different type of tax basis.
b. In the Personal Finance section the IRA program now handles explicit
inflation input and withdrawal tax rate input and the Stock Portfolio program
handles stock prices with decimal fractions rather than fractions expressed in
terms of eighths.
3. Market data (i.e.: interest rates; real estate values, growth rates and rents; taxes;
expenses; etc.) used in the examples in this book do not necessarily represent
typical current actual data, or reflect recent market trends.
It can be mutually advantageous to both borrower and lender to refinance an existing
mortgage which has an interest rate substantially below the current market rate, with a
loan at a below-market rate. The borrower has the immediate use of tax-free cash, while
the lender has substantially increased debt service on a relatively small cash outlay.
To find the benefits to both borrower and lender:
1. Calculate the monthly payment on the existing mortgage.
2. Calculate the monthly payment on the new mortgage.
3. Calculate the net monthly payment received by the lender (and paid by the borrower)
by adding the figure found in Step 1 to the figure found in Step 2.
4. Calculate the Net Present Value (NPV) to the lender of the net cash advanced.
5. Calculate the yield to the lender as an IRR.
6. Calculate the NPV to the borrower of the net cash received.
Example: An investment property has an existing mortgage which originated 8 years ago
with an original term of 25 years, fully amortized in level monthly payments at 6.5%
interest. The current balance is $133,190.
Although the going current market interest rate is 11.5%, the lender has agreed to
refinance the property with a $200,000, 17 year, level-monthly-payment loan at 9.5%
interest.
What are the NPV and effective yield to the lender on the net amount of cash actually
advanced?
What is the NPV to the borrower on this amount if he can earn a 15.25% equity yield rate
on the net proceeds of the loan?
12c platinum / 12C
RPN Keystrokes
gÂ
fCLEARG
17gA
6.5gC
133190$ P?0
12c platinum
ALG Keystrokes
gÂ
fCLEARG
17gA
6.5gC
133190$ P?0
Display Comments
-1,080.33
Monthly payment on
existing mortgage
received by lender.
7
8 Real Estate
12c platinum / 12C
RPN Keystrokes
9.5gC
200000Þ$
P
:0+P +:0P
:$ :$
133190+?0 +133190³?0
11.5gC$ 11.5gC$$
:0- -:0³
:0$¼ :0$¼
12§ §12³
15.25gC$ 15.25gC$$
:0- -:0³
12c platinum
ALG Keystrokes
9.5gC
200000Þ$P
Display Comments
1,979.56
899.23
-66,810.00
-80,425.02
-13,615.02
14.83
-65,376.72
1,433.28
Monthly payment on
new mortgage.
Net monthly payment (to
lender).
Net amount of cash
advanced (by lender).
Present value of net
monthly payment.
NPV to lender of net
cash advanced.
% nominal yield (IRR).
Present value of net
monthly payment at
15.25%.
NPV to borrower.
Wrap-Around Mortgage
A wrap-around mortgage is essentially the same as a refinancing mortgage, except that the
new mortgage is granted by a different lender, who assumes the payments on the existing
mortgage, which remains in full force. The new (second) mortgage is thus "wrapped
around" the existing mortgage. The "wrap-around" lender advances the net difference
between the new (second) mortgage and the existing mortgage in cash to the borrower,
and receives as net cash flow, the difference between debt service on the new (second)
mortgage and debt service on the existing mortgage.
When the terms of the original mortgage and the wrap-around are the same, the
procedures in calculating NPV and IRR to the lender and NPV to the borrower are exactly
the same as those presented in the preceding section on refinancing.
Example 1: A mortgage loan on an income property has a remaining balance of
$200,132.06. When the load originated 8 years ago, it had a 20 year term with full
amortization in level monthly payments at 6.75% interest.
A lender has agreed to "wrap" a $300,000 second mortgage at 10%, with full amortization
in level monthly payments over 12 years. What is the effective yield (IRR) to the lender
on the net cash advanced?
Real Estate 9
PV
PMT
B
PV
PMT
12c platinum / 12C
RPN Keystrokes
gÂ
fCLEARG
20\
8-gA
12c platinum
ALG Keystrokes
gÂ
fCLEARG
208³gA
Display Comments
144.00
Total number of months
remaining in original loan
(into n).
Net cash advanced (into PV).
Nominal yield (IRR) to lender
(calculated).
Sometimes the wrap around mortgage will have a longer payback period than the original
mortgage, or a balloon payment may exist.
1
AL
for n2 Years
(+)
2
(–)
......
for n1 Years
1
2
10 Real Estate
Where:
= number of years remaining in original mortgage
n
1
PMT
= yearly payment of original mortgage
1
= remaining balance of original mortgage
PV
1
n
= number of years in wrap-around mortgage
2
= yearly payment of wrap-around mortgage
PMT
2
PV
= total amount of wrap-around mortgage
2
BAL = balloon payment
Example 2: A customer has an existing mortgage with a balance of $125,010, a
remaining term of 200 months, and a $1051.61 monthly payment. He wishes to obtain a
$200,000, 9 ½% wrap-around with 240 monthly payments of $1681.71 and a balloon
payment at the end of the 240th month of $129,963.35. If you, as a lender, accept the
proposal, what is your rate of return?
$125010
$1681.71 $1681.71 $1681.71
240 mos.
$ 129963.35
......
$ -1051.61
200 mos.
$ -200000
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARG fCLEARG
200000Þ\ 200000Þ
125010+gJ+125010gJ
1051.61Þ\ 1051.61Þ
1681.71+ +1681.71gK
$ -1051.61
12c platinum
ALG Keystrokes
Display Comments
-74,990.00
630.10
Net investment.
Net cash flow
received by lender.
Real Estate 11
12c platinum / 12C
RPN Keystrokes
gK99ga
~gK
~ga
~gK
2ga
gFgK
39ga 39ga
~129963.35+ ~+129963.35
gK gK
fL12§ fL§12³
If you, as a lender, know the yield on the entire transaction, and you wish to obtain the
payment amount on the wrap-around mortgage to achieve this yield, use the following
procedure. Once the monthly payment is known, the borrower's periodic interest rate may
also be determined.
1.
Press the g and press fCLEARG.
2.
Key in the remaining periods of the original mortgage and press n.
3.
Key in the desired annual yield and press gC.
4. Key in the monthly payment to be made by the lender on the original mortgage and
press ÞP.
5.
Press $.
6.
RPN: Key in the net amount of cash advanced and press +Þ$.
6.
ALG: Press +, key in the net amount of cash advanced and press ³Þ$.
7.
Key in the total term of the wrap-around mortgage and press n.
8.
If a balloon payment exists, key it in and press M.
9.
Press P to obtain the payment amount necessary to achieve the desired yield.
10.
Key in the amount of the wrap-around mortgage and press Þ$¼ to obtain the
borrower's periodic interest rate.
Example 3: Your firm has determined that the yield on a wrap-around mortgage should
be 12% annually. In the previous example, what monthly payment must be received to
achieve this yield on a $200,000 wrap-around? What interest rate is the borrower paying?
12c platinum
ALG Keystrokes
99ga
~gK
~ga
~gK
2ga
1681.71gK
Display Comments
1,681.71
39.00
131,645.06
11.84
The above cash flow
occurs 200 times.
Next cash flow
received by lender.
Cash flow occurs 39
times.
Final cash flow.
Rate of return to
lender.
12 Real Estate
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARG fCLEARG
200n12gC 200n12gC
1051.61ÞP 1051.61ÞP
$74990+ $+74990³
Þ$ Þ$
240n 240n
129963.35MP 129963.35MP
200000Þ$¼ 200000Þ$¼
12§ §12³
12c platinum
ALG Keystrokes
Display Comments
-165,776.92
1,693.97
9.58
Number of periods and
monthly interest rate.
Monthly payment.
Present value of
payments plus cash
advanced.
Monthly payment
received by lender.
Annual interest rate paid
by borrower.
Income Property Cash Flow Analysis
Before-Tax Cash Flows
The before-tax cash flows applicable to real estate analysis and problems are:
• Potential Gross Income
• Effective Gross Income
• Net Operating Income (also called Net Income Before Recapture)
• Cash Throw-off to Equity (also called Gross Spendable Cash)
The derivation of these cash flows follows a set sequence:
1. Calculate Potential Gross Income by multiplying the rent per unit times the number
of units, times the number of rental payment periods per year. This gives the rental
income the property would generate if it were fully occupied.
2. Deduct Allowance for Vacancy and Rental Loss. This is usually expressed as a
percentage. The result is Rent Collections (which is also Effective Gross Income if
there is no "Other Income").
3. Add "Other Income" such as receipts from concessions (laundry equipment, etc.),
produced from sources other than the rental office space. This is Effective Gross
Income.
4. Deduct Operating Expenses. These are expenditures the landlord-investor must
make, by contract or custom, to preserve the property and keep in capable of
producing the gross income. The result is the Net Operating Income.
5. Deduct Annual Debt Service on the mortgage. This produces Cash Throw-Off to
Equity.
Real Estate 13
Thus:
Effective Gross Income =Potential Gross Income - Vacancy Loss + Other Income.
Net Operating Income =Effective Gross Income - Operating Expenses.
Cash Throw-Off =Net Operating Income - Annual Dept Service.
Example: A 60 unit apartment building has rentals of $250 per unit per month. With a
5% vacancy rate, the annual operating cost is $76,855.
The property has just been financed with a $700,000 mortgage, fully amortized in a level
monthly payments at 11.5% over 20 years.
Potential Gross Income.
Effective Gross Income.
Net Operating Income.
Annual Debt Service.
Cash Throw-Off.
Before-Tax Reversions (Resale Proceeds)
The reversion receivable at the end of the income projection period is usually based on
forecast or anticipated resale of the property at that time. The before tax reversion amount
applicable to real estate analysis and problems are:
• Sale Price.
• Cash Proceeds of Resale.
• Outstanding Mortgage Balance.
• Net Cash Proceeds of Resale to Equity.
The derivation of these reversions is as follows:
1. Forecast or estimate Sales Price. Deduct sales and Transaction Costs. The result is
the Proceeds of Resale.
14 Real Estate
2. Calculate the Outstanding Balance of the Mortgage at the end of the Income
Projection Period and subtract it from Proceeds of Resale. The result is Net Cash
Proceeds of Resale.
Thus:
Cash Proceeds of Resale = Sales Price - Transaction Costs.
Net Cash Proceeds of Resale = Cash Proceeds of Resale - Outstanding Mortgage Balance.
Example: The apartment property in the preceding example is expected to be resold in 10
years. The anticipated resale price is $800,000. The transaction costs are expected to be
7% of the resale price. The mortgage is the same as that indicated in the preceding
example.
• What will the Mortgage Balance be in 10 years?
• What are the Cash Proceeds of Resale and Net Cash Proceeds of Resale?
Mortgage term.
Mortgage rate.
Property value.
Monthly payment.
Projection period.
Mortgage balance in 10 years.
Estimated resale.
Cash Proceeds of Resale.
Net Cash Proceeds of Resale.
After-Tax Cash Flows
The After-Tax Cash Flow (ATCF) is found for the each year by deducting the Income
Tax Liability for that year from the Cash Throw Off.
Where Taxable Income = Net Operating Income - interest - depreciation,
Tax Liability = Taxable Income x Marginal Tax Rate,
and After Tax Cash Flow = Cash Throw Off - Tax Liability.
The After-Tax Cash Flow for the initial and successive years may be calculated by the
following HP 12C Platinum program. This program calculates the Net Operating Income
using the Potential Gross Income, operational cost and vacancy rate. The Net Operating
Real Estate 15
income is readjusted each year from the growth rates in Potential Gross Income and
operational costs.
The user is able to change the method of finding the depreciation from declining balance
to straight line. To make the change, key in fV at line 032 (ALG: 026) of the
program in place of f#.
12c platinum / 12C
RPN KEYSTROKES
fs
fCLEARÎ
0
n
?1
:7
Æ
2
z
?7
1
?+1
1
2
f!
?0
:5
n
:¼
:6
¼
d
?6
d
:$
:4
$
d
?4
d
gm
g(036
:1
f#
?-0
(If any of the values are not known, they should be solved for.)
3.
Key in Potential Gross Income (PGI) and press ?2.
4.
Key in Operational cost and press ?3.
5.
Key in depreciable value and press ?4.
6.
Key in depreciable life and press ?5.
7.
Key in factor (for declining balance only) and press ?6.
8.
Key in the Marginal Tax Rate (as a percentage) and press ?7.
9. Key in the growth rate in Potential Gross Income (0 for no growth) and press
?8.
10.
Key in the growth rate in operational cost (0 if no growth) and press ?9.
11.
Key in the vacancy rate (0 for no vacancy rate) and press ?.0.
12. RPN: Key in the desired depreciation function at line 032 in the program.
12. ALG: Key in the desired depreciation function at line 026 in the program.
13.
Press t to compute ATCF. The display will pause showing the year and then
will stop with the ATCF for that year. The Y-register contains the year.
14.
Continue pressing t to compute successive After-Tax Cash Flows.
Example 1: A triplex was recently purchased for $100,000 with a 30 year loan at 12.25%
and a 20% down payment. Not including a 5% annual vacancy rate, the potential gross
income is $9,900 with an annual growth rate of 6%. Operating expenses are $3,291.75
with a 2.5% growth rate. The depreciable value is $75,000 with a projected useful life of
$20 years. Assuming a 125% declining balance depreciation, what are the After-Tax Cash
Flows for the first 10 years if the investors Marginal Tax Rate is 35%?
1st year operating cost.
Depreciable value.
Useful life.
Declining balance factor.
Marginal Tax Rate.
Potential Gross Income
growth rate.
2.5?9 2.5?9
5?.0 5?.0
t t
t t
t t
t t
t t
t t
t t
t t
t t
t t
2.50
5.00
1.00
-1,020.88
2.00
-822.59
3.00
-598.85
4.00
-348.94
5.00
-72.16
6.00
232.35
7.00
565.48
8.00
928.23
9.00
1,321.62
10.00
1,746.81
Operating cost growth.
Vacancy rate.
Year 1
1
Year 2
2
Year 3
3
Year 4
4
Year 5
5
Year 6
6
Year 7
7
Year 8
8
Year 9
9
Year 10
10
Example 2: An office building was purchased for $1,400,000. The value of depreciable
improvements is $1,200,000 with a 35 year economic life. Straight line depreciation will
be used. The property is financed with a $1,050,000 loan. The terms of the loan are 9.5%
interest and $9,173.81 monthly payments for 25 years. The office building generates a
Potential Gross Income of $175,200 which grows at a 3.5% annual rate. The operating
cost is $40,296.00 with a 1.6% annual growth rate. Assuming a Marginal Tax Rate of
50% and a vacancy rate of 7%, what are the After-Tax Cash Flows for the first 5 years?
Real Estate 19
12c platinum / 12C
RPN Keystrokes
gÂ
fCLEARH
1050000$
9173.81ÞP
9.5gC
25gA
175200?2 175200?2
40296?3 40296?3
1200000?4 1200000?4
35?5 35?5
50?7 50?7
3.5?8 3.5?8
1.6?9 1.6?9
7?.0 7?.0
g(031 g(025
fsfV fsfV
fst fst
t t
t t
t t
t t
12c platinum
ALG Keystrokes
gÂ
fCLEARH
1050000$
9173.81ÞP
9.5gC
25gA
Display Comments
175,200.00
40,296.00
1,200,000.00
35.00
50.00
3.50
1.60
7.00
7.00
032, 42 23
026, 42 23
1.00
18,021.07
2.00
20,014.26
3.00
22,048.90
4.00
24,123.14
5.00
26,234.69
Potential Gross
Income.
1st year operating
cost.
Depreciable value.
Depreciable life.
Marginal tax rate.
Potential Gross
Income growth rate.
Operating cost
growth rate.
Vacancy rate.
Go to dep. step.
RPN:Change to SL
ALG:depreciation
Year 1
ATCF1
Year 2
ATCF2
Year 3
ATCF3
Year 4
ATCF4
Year 5
ATCF5
After-Tax Net Cash Proceeds of Resale
The After-Tax Net Cash Proceeds of Resale (ATNCPR) is the after-tax reversion to
equity; generally, the estimated resale price of the property less commissions, outstanding
debt and any tax claim.
The After-Tax Net Cash Proceeds can be found using the HP 12C Platinum program
which follows.
20 Real Estate
This program uses declining balance depreciation to find the amount of depreciation from
purchase to sale. This amount is used to determine the excess depreciation (which is equal
to the amount of actual depreciation minus the amount of the straight line depreciation).
The Marginal Tax Rate (MTR) that the user inputs is applied to this excess depreciation.
The Capital Gains Tax Rate (CGTR) that the user inputs is applied to the capital gain
from purchase to sale less the expenses of sale (i.e. the NCPR or Net cash Proceeds of
Resale), plus the straight line depreciation.
The user may change to a different depreciation method by keying in the desired function
at line 026 (ALG: 029) in place of f#.
In addition the user may nullify the straight line depreciation by keying in a 0 at line 035
(ALG: 039) in place of fV. This means that all of the actual depreciation from
purchase to sale is then treated as "excess" or unrecaptured depreciation. This is
illustrated below in Example 2.
12c platinum / 12C
RPN KEYSTROKES
fs
fCLEARÎ
gÂ
?2
gA
d
b
-
?0
~
-
:7
b
?1
:P
fB
P
M
?+0
fCLEARG
:3
$
:4
n
:5
¼
:2
f#
d
n: Used i: Used PV: Used PMT: Used
FV: Used R0: NCPR R
: Tax paid R2: Desired yr.
1
R3: Dep. value R4: Dep. life R5: Factor R6: MTR
R7: CGTR R8-R.3: Unused
Program Instructions:
1.
Key in the program and press fCLEARH.
22 Real Estate
2. Key in the loan values:
(If any of the values are unknown, they should be solved for and if one has
to be solved for then the correct payment mode needs to be set)
3.
4.
5. Key in accelerated depreciation factor for the declining balance method and press
6.
7.
8.
9.
10.
11.
12.
Example 1: An apartment complex, purchased for $900,000 ten years ago, is sold for
$1,750,000. The closing cost is 8% of the sale price, the income tax rate is 48% and the
capital gains tax rate is 19.2%.
A $700,000 loan for 20 years at 9.5% annual interest was used to purchase the complex.
When it was purchased the depreciable value was $750,000 with a useful life of 25 years.
Using 125% declining balance depreciation, what are the After-Tax Net Cash Proceeds in
year 10?
• Key in annual interest rate and press gC.
• Key in mortgage amount and press $.
• Key in monthly payment and press ÞP.
Key in depreciable value and press ?3.
Key in depreciable life in years and press ?4.
?5.
Key in your Marginal Tax Rate as a percentage and press ?6.
Key in the Capital Gains Tax Rate as a percentage and press ?7.
Key in the purchase price and press \(³).
Key in the sale price and press \(³).
Key in the % commission charged on the sale and press \(³).
RPN: If a dollar value is desired instead of a commission rate, key in gÂ,
which does not affect the register values, at line 005 of the program.
ALG: If a dollar value is desired instead of a commission rate, key in gÂ,
which does not affect the register values, at line 008 of the program.
Key in the number of years after purchase and press t. The ATNCPR is
displayed.
To see the NCPR press :0 and to see the tax due press :1.
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARH fCLEARH
700000$ 700000$
9.5gC 9.5gC
20gA 20gA
PPP
750000?3 750000?3
12c platinum
ALG Keystrokes
Display Comments
0.00
700,000.00
0.79
240.00
-6,524.92
750,000.00
Mortgage.
Monthly interest.
Number of
payments.
Monthly payment.
Depreciable value.
Real Estate 23
A
A
12c platinum / 12C
RPN Keystrokes
25?4 25?4
125?5 125?5
48?6 48?6
19.2?7 19.2?7
12c platinum
ALG Keystrokes
Display Comments
25.00
125.00
48.00
19.20
Depreciable life.
Factor.
Marginal Tax Rate.
Capital Gains Tax
Rate.
900000\ 900000³
1750000\ 1750000³
8\ 8³
10t 10t
:0 :0
:1 :1
900,000.00
1,750,000.00
8.00
911,372.04
1,105,746.74
194,374.70
Purchase price.
Sale price.
Commission rate.
TNCPR.
NCPR.
Tax due on resale.
Example 2: Now, re-do the previous example assuming all depreciation is treated as
excess or unrecaptured depreciation, with MTR=25% and CGTR=15%.
First the fV in the program must be replaced with 0. This may be done as follows:
Monthly payment.
Marginal Tax Rate.
Capital Gains Tax
Rate.
900,000.00
1,750,000.00
8.00
924,009.92
1,105,746.74
181,736.83
Purchase price.
Sale price.
Commission rate.
TNCPR.
NCPR.
Tax due on resale.
Lending
Loan With a Constant Amount Paid Towards
Principal
This type of loan is structured such that the principal is repaid in equal installments with
the interest paid in addition. Therefore each periodic payment has a constant amount
applied toward the principle and a varying amount of interest.
Loan Reduction Schedule
If the constant periodic payment to principal, annual interest rate, and loan amount are
known, the total payment, interest portion of each payment, and remaining balance after
each successive payment may be calculated as follows:
RPN Mode:
1.
Key in the constant periodic payment to principal and press ?0.
2.
Key in periodic interest rate and press \\\.
3. Key in the loan amount. If you wish to skip to another time period, press \.
Then key in the number of payments to be skipped, and press :0§-.
4.
Press ~b to obtain the interest portion of the payment.
5.
Press :0+ to obtain the total payment.
6.
Press O:0- to obtain the remaining balance of the loan.
7. Return to step 4 for each successive payment.
ALG Mode:
1.
Key in the constant periodic payment to principal and press ?0.
2.
Key in the loan amount and press ?1.
3.
Key in periodic interest rate and press ?2.
If you wish to skip to another time period, key in the number of payments to be
skipped, and press §:0³?-1.
4.
Press :1§:2b+ to obtain the interest portion of the payment.
5.
Press :0?-1³ to obtain the total payment.
6.
Press :1 to obtain the remaining balance of the loan.
7. Return to step 4 for each successive payment.
24
Lending 25
Example 1: A $60,000 land loan at 10% interest calls for equal semi-annual principal
payments over a 6-year maturity. What is the loan reduction schedule for the first year?
(Constant payment to principal is $5000 semi-annually). What is the fourth year's
schedule (skip 4 payments)?
Semi-annual interest rate.
First payment's interest.
Total first payment.
Remaining balance.
Second payment's interest.
Total second payment.
Remaining balance after
the first year.
Seventh payment's interest.
Total seventh payment.
Remaining balance.
Eighth payment's interest.
Total eighth payment.
Remaining balance after
fourth year.
Add-On Interest Rate Converted to APR
An add-on interest rate determines what portion of the principal will be added on for
repayment of a loan. This sum is then divided by the number of months in a loan to
determine the monthly payment. For example, a 10% add-on rate for 36 months on $3000
means add one-tenth of $3000 for 3 years (300 x 3) - usually called the "finance charge" for a total of $3900. The monthly payment is $3900/36.
This keystroke procedure converts an add-on interest rate to a annual percentage rate
when the add-on rate and number of months are known.
26 Lending
RPN Mode:
1.
Press g and press fCLEARG .
2.
Key in the number of months in the loan and press n\:gA .
3.
Key in the add-on rate and press §.
4.
Key in the amount of the loan and press $
5.
Press ~zÞP.
6.
Press ¼12§ to obtain the APR.
ALG Mode:
1.
Press g and press fCLEARG .
2.
Key in the number of months in the loan and press n³:gA§ .
3.
Key in the add-on rate and press ³ .
4.
Key in the amount of the loan and press $
5.
Press ~³ÞP .
6.
Press ¼§12³ to obtain the APR.
Example 1: Calculate the APR and monthly payment of a 12% $1000 add-on loan which
has a life of 18 months.
This HP 12C Platinum program calculates the monthly payment amount, credit life
amount (an optional insurance which cancels any remaining indebtedness at the death of
the borrower), total finance charge, and annual percentage rate (APR) for an add-on
interest rate (AIR) loan. The monthly payment is rounded (in normal manner) to the
nearest cent. If other rounding techniques are used, slightly different results may occur.
Key in the number of monthly payments in the loan and press ?0.
4.
Key in the annual add-on interest rate as a percentage and press ?1.
5.
Key in the credit life as a percentage and press ?2.
6.
Key in the loan amount and press ?3.
7.
Press t to find the monthly payment amount.
8.
Press t to obtain the amount of credit life.
30 Lending
9.
Press t to calculate the total finance charge.
10.
Press t to calculate the annual percentage rate.
11. For a new loan return to step 3.
Example 1: You wish to quote a loan on a $3100 balance, payable over 36 months at an
add-on rate of 6.75%. Credit life (CL) is 1%. What are the monthly payment amount,
credit life amount, total finance charge, and APR?
12c platinum / 12C
RPN Keystrokes
fCLEARGfCLEARG
36?0 36?0
6.75?1 6.75?1
1?2 1?2
3100?3 3100?3
t t
t t
t t
t t
12c platinum
ALG Keystrokes
Display Comments
36.00
6.75
1.00
3100.00
-107.42
116.02
-651.10
12.39
Months.
Add-on interest rate.
Credit life (%).
Loan.
Monthly payment.
Credit life.
Total finance charge.
APR.
Interest Rebate - Rule of 78's
This procedure finds the unearned interest rebate, as well as the remaining principal
balance due for a prepaid consumer loan using the Rule of 78's. The known values are the
current installment number, the total number of installments for which the loan was
written, and the total finance charge (amount of interest). The information is entered as
follows:
RPN Mode:
1.
Key in number of months in the loan and press ?1.
2.
Key in payment number when prepayment occurs and press -?2 1+.
3.
Key in total finance charge and press §:1\§:1+z:2§ to
obtain the unearned interest (rebate).
4.
Key in periodic payment amount and press :2§~- to obtain the amount of
principal outstanding.
ALG Mode:
1.
Key in number of months in the loan and press ?1-.
2.
Key in payment number when prepayment occurs and press³?2+1§.
3.
Key in total finance charge and press ³:1g’+:1z~~§:2 ³ to obtain the unearned interest (rebate).
4.
Key in periodic payment amount and press §:2-~³ to obtain the amount
of principal outstanding.
Lending 31
Example 1: A 30 month $1000 loan having a finance charge of $180, is being repaid at
$39.33 per month. What is the rebate and balance due after the 25th regular payment?
12c platinum / 12C
RPN Keystrokes
30?1 30?1
25-?2 -25³?2
1+180§+1§180³
:1\ :1g’+:1
§:1+
z:2§ :2³
39.33:2§ 39.33§:2
~- -~³
The following HP 12C Platinum program can be used to evaluate the previous example.
Key in the number of months in the loan and press \(³).
3.
Key in the payment number when prepayment occurs and press \(³).
4.
Key in the total finance charge and press t to obtain the unearned interest
(rebate).
5.
Key in the periodic payment amount and press t to find the amount of principal
outstanding.
6. For a new case return to step 2.
12c platinum / 12C
RPN Keystrokes
30\ 30³
25\ 25³
180t 180t
39.33t 39.33t
DISPLAY
026,43,33,000
12c platinum
ALG Keystrokes
12c platinum
ALG KEYSTROKES
~
³
g(000
fs
Display Comments
5.81
190.84
Rebate.
Outstanding principal.
DISPLAY
026, 34
027, 36
028,43,33,000
Graduated Payment Mortgages
The Graduated Payment Mortgage is designed to meet the needs of young home buyers
who currently cannot afford high mortgage payments, but who have the potential of
increasing earning in the years to come.
Under the Graduated Payment Mortgage plan, the payments increase by a fixed
percentage at the end of each year for a specified number of years. Thereafter, the
payment amount remains constant for remaining life of the mortgage.
The result is that the borrower pays a reduced payment (a payment which is less than a
traditional mortgage payment) in the early years, and in the later years makes larger
payments than he would with a traditional loan. Over the entire term of the mortgage, the
borrower would pay more than he would with conventional financing.
Lending 33
Given the term of the mortgage (in years), the annual percentage rate, the loan amount,
the percentage that the payments increase, and the number of years that the payments
increase, the following HP 12C Platinum program determines the monthly payments and
remaining balance for each year until the level payment is reached.
n: Used i: i/12 PV: Used PMT: Used
FV: Used R0: Used R1: Used R2: Used
R3: Used R4: Level Pmt. R5-R9: Unused
Program Instructions:
1. Key in the program.
2.
Press fCLEARH.
3.
Key in the term of the loan and press n.
4.
Key in the annual interest rate and press ¼.
5.
Key in the total loan amount and press $.
6.
Key in the rate of graduation (as a percent) and press \(³).
7.
Key in the number of years for which the loan graduates and press t. The
following information will be displayed for each year until a level payment is
reached.
a. The current year.
Then press t to continue.
b. The monthly payment for the current year.
Then press t to continue.
c. The remaining balance to be paid on the loan at the end of the current year.
Then press t to return to step a. unless the level payment is reached.
If the level payment has been reached, the program will stop, displaying
the monthly payment over the remaining term of the loan.
8.
For a new case press g(000 and return to step 2.
Example: A young couple recently purchased a new house with a Graduated Payment
Mortgage. The loan is for $50,000 over a period of 30 years at an annual interest rate of
12.5%. The monthly payments will be graduating at an annual rate of 5% for the first 5
years and then will be level for the remaining 25 years. What are the monthly payment
amount for the first 6 years?
12c platinum / 12C
RPN Keystrokes
fCLEARHfCLEARH
30n 30n
12.5¼ 12.5¼
50000$ 50000$
5\ 5³
5t 5t
t t
t t
t t
t t
t t
12c platinum
ALG Keystrokes
Display Comments
0.00
30.00
12.50
50,000.00
5.00
1.00
-448.88
-50,914.67
2.00
-471.33
-51,665.07
Term
Annual interest rate
Loan amount
Rate of graduation
Year 1
1st year monthly payment.
Remaining balance after 1st
year.
Year 2
2nd year monthly payment.
Remaining balance after 2nd
year.
36 Lending
12c platinum / 12C
RPN Keystrokes
t t
t t
t t
t t
t t
t t
t t
t t
t t
t t
12c platinum
ALG Keystrokes
Display Comments
3.00
-494.89
-52,215.34
4.00
-519.64
-52,523.86
5.00
-545.62
-52,542.97
-572.90
Year 3
3rd year monthly payment.
Remaining balance after 3rd
year.
Year 4
4th year monthly payment.
Remaining balance after 4th
year.
Year 5
5th year monthly payment.
Remaining balance after 5th
year.
Monthly payment for
remainder of term.
Variable Rate Mortgages
As its name suggests, a variable rate mortgage is a mortgage loan which provides for
adjustment of its interest rate as market interest rates change. As a result, the current
interest rate on a variable rate mortgage may differ from its origination rate (i.e., the rate
when the loan was made). This is the difference between a variable rate mortgage and the
standard fixed payment mortgage, where the interest rate and the monthly payment are
constant throughout the term.
Under the agreement of the variable rate mortgage, the mortgage is examined periodically
to determine any rate adjustments. The rate adjustment may be implemented in two ways:
1. Adjusting the monthly payment.
2. Modifying the term of the mortgage.
The period and limits to interest rate increases vary from state to state.
Each periodic adjustment may be calculated by using the HP 12C Platinum with the
following keystroke procedure. The original terms of the mortgage are assumed to be
known.
1.
Press g and press fCLEARG.
2.
Key in the remaining balance of the loan and press $.
The remaining balance is the difference between the loan amount and the total
principal from the payments which have been made.
To calculate the remaining balance, do the following:
a. Key in the previous remaining balance. If this is the first mortgage adjustment,
this value is the original amount of the loan. Press $.
b. Key in the annual interest rate before the adjustment (as a percentage) and press
gC.
Lending 37
c. Key in the number of years since the last adjustment. If this is the first mortgage
adjustment, then key in the number of years since the origination of the mortgage.
Press gA.
d.
Key in the monthly payment over this period and press ÞP.
e.
Press M to find the remaining balance, then press fCLEARGÞ$.
3.
Key in the adjusted annual interest rate (as a percentage) and press gC.
To calculate the new monthly payment:
a.
Key in the remaining life of the mortgage (years) and press gA.
b.
RPN: Press P to find the new monthly payment.
b.
ALG: Press PP to find the new monthly payment.
To calculate the revised remaining term of the mortgage:
a.
Key in the present monthly payment and press P.
b.
RPN: Press n12z to find the remaining term of the mortgage in years.
b.
ALG: Press nz12³ to find the remaining term of the mortgage in years.
Example: A homeowner purchased his house 3 years ago with a $50,000 variable rate
mortgage. With a 30 year term, his current monthly payment is $495.15. When the
interest rate is adjusted from 11.5% to 11.75%, what will the monthly payment be? If the
monthly payment remained unchanged, find the revised remaining term on the mortgage.
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARG fCLEARG
50000$ 50000$
11.5gC 11.5gC
3gA 3gA
495.15ÞP 495.15ÞP
M M
fCLEARG fCLEARG
Þ$ Þ$
11.75gC 11.75gC
30\3- 30-3³
gA gA
P PP
495.15ÞP 495.15ÞP
n12z nz12³
12c platinum
ALG Keystrokes
Display Comments
50,000.00
0.96
36.00
-495.15
-49,316.74
49,316.74
0.98
27.00
324.00
-504.35
-495.15
31.67
Original amount of loan.
Original monthly interest rate.
Period.
Previous monthly payment.
Remaining balance.
Adjusted monthly interest.
Remaining life of mortgage.
New monthly payment.
Previous monthly payment.
New remaining term (years).
38 Lending
Skipped Payments
Sometimes a loan (or lease) may be negotiated in which a specific set of monthly
payments are going to be skipped each year. Seasonally is usually the reason for such an
agreement. For example, because of heavy rainfall, a bulldozer cannot be operated in
Oregon during December, January, and February, and the lessee wishes to make payments
only when his machinery is being used. He will make nine payments per year, but the
interest will continue to accumulate over the months in which a payment is not made.
To find the monthly payment amount necessary to amortize the loan in the specified
amount of time, information is entered as follows:
1.
Press g and press fCLEARG.
2. Key in the number of the last payment period before payments close the first time
and press n.
3.
Key in the annual interest rate as a percentage and press gC1PM.
RPN Mode:
4.
Press Þ$12:n-n0PM?0:n.
5.
Key in the number of payments which are skipped and press n1P0$M?+0.
6.
Press 0P12n100$M:$+ÞfCLEARG¼
7.
Key in the total number of years in the loan and press n.
8.
Key in the loan amount and press $P:0z to obtain the monthly payment
amount when the payment is made at the end of the month.
9.
Press ÞM0P1n.
10.
Key in the annual interest rate as a percent and press gC$ to find the
monthly payment amount when the payment is made at the beginning of the month.
ALG Mode:
4.
Press Þ$12-:nn0PM?0:n-.
5. Key in the number of payments which are skipped and press
n1P0$M?+0.
6.
Press 0P12n100$M+:$³ÞfCLEARG¼
7.
Key in the total number of years in the loan and press n.
8.
Key in the loan amount and press $Pz:0³ to obtain the monthly
payment amount when the payment is made at the end of the month.
9.
Press ÞM0P1n.
10.
Key in the annual interest rate as a percent and press gC$$ to find the
monthly payment amount when the payment is made at the beginning of the month.
Lending 39
Example: A bulldozer worth $100,000 is being purchased in September. The first
payment is due one month later, and payments will continue over a period of 5 years. Due
to the weather, the machinery will not be used during the winter months, and the
purchaser does not wish to make payments during January, February, and March (months
4 thru 6). If the current interest rate is 14%, what is the monthly payment necessary to
amortize the loan?
Number of payments made
before a group of payments is
skipped.
Monthly interest rate.
FV of 3 monthly unit PMTs.
FV of 6 monthly unit PMTs.
Effective annual interest rate
Monthly payment in arrears.
Savings
Initial Deposit with Periodic Deposits
Given an initial deposit into a savings account, and a series of periodic deposits coincident
with the compounding period, the future value (or accumulated amount) may be
calculated as follows:
1. Press g and press fCLEARG.
2. Key in the initial investment and press Þ$.
3. Key in the number of additional periodic deposits and press n.
4. Key in the periodic interest rate and press ¼.
5. Key in the periodic deposit and press ÞP.
6. Press M to determine the value of the account at the end of the time period.
Example: You have just opened a savings account with a $200 deposit. If you deposit
$50 a month, and the account earns 5 ¼ % compounded monthly, how much will you
have in 3 years?
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARG fCLEARG
200Þ$ 200Þ$
3gA 3gA
5.25gC 5.25gC
50ÞPM 50ÞPM
Note: If the periodic deposits do not coincide with the compounding periods, the account
must be evaluated in another manner. First, find the future value of the initial deposits and
store it. Then use the procedure for compounding periods different from payment periods
to calculate the future value of the periodic deposits. Recall the future value of the initial
deposit and add to obtain the value of the account.
40
12c platinum
ALG Keystrokes
Display Comments
2,178.94
Value of the account.
Savings 41
Number of Periods to Deplete a Savings
Account or to Reach a Specified Balance
Given the current value of a savings account, the periodic interest rate, the amount of the
periodic withdrawal, and a specified balance, this procedure determines the number of
periods to reach that balance (the balance is zero if the account is depleted).
1. Press g and press fCLEARG.
2. Key in the value of the savings account and press Þ$.
3. Key in the periodic interest rate and press ¼.
4. Key in the amount of the periodic withdrawal and press P.
5. Key in the amount remaining in the account and press M.
This step may be omitted if the account is depleted (FV=0).
6. Press n to determine the number of periods to reach the desired balance.
Example: Your savings account presently contains $18,000 and earns 5 ½% compounded
monthly. You wish to withdraw $300 a month until the account is depleted. How long
will this take? If you wish to reduce the account to $5000, how many withdrawals can you
make?
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARG fCLEARG
18000Þ$ 18000Þ$
5.5gC 5.5gC
300Pn 300Pn
5000Mn 5000Mn
12c platinum
ALG Keystrokes
Display Comments
71.00
53.00
Months to deplete account.
Months to reduce the account to
$5000.
42 Savings
PV
FV
Periodic Deposits and Withdrawals
This section is presented as a guideline for evaluating a savings plan when deposits and
withdrawals occur at irregular intervals. One problem is given, and a step by step method
for setting up and solving the problem is presented:
Example: You are presently depositing $50 and the end of each month into a local
savings and loan, earning 5 ½% compounded monthly. Your current balance is $1023.25.
How much will you have accumulated in 5 months?
The cash flow diagram looks like this:
= ?
1 3452
-50-50-50- 50 -50
= - 1023.25
12c platinum / 12C
RPN Keystrokes
g gÂ
fCLEARG fCLEARG
50ÞP 50ÞP
5.5gC 5.5gC
1023.25Þ$ 1023.25Þ$
5nM 5nM
Now suppose that at the beginning of the 6th month you withdrew $80.
What is the new balance?
12c platinum / 12C
RPN Keystrokes
80- -80³
12c platinum
ALG Keystrokes
12c platinum
ALG Keystrokes
Display Comments
1,299.22
Display Comments
1,219.22
Amount in account.
New balance.
Savings 43
PV
FV
FV
PV
You increase your monthly deposit to $65. How much will you have in 3 months?
The cash flow diagram looks like this:
= ?
1 3 2
-65-65-65
= - 1219.22
12c platinum / 12C
RPN Keystrokes
Þ$Þ$
65ÞP 65ÞP
3nM 3nM
Suppose that for 2 months you decide not to make a periodic deposit. What is the balance
in the account?
12c platinum
ALG Keystrokes
Display Comments
1,431.95
= ?
Account balance.
1 2
= - 1431.95
12c platinum / 12C
RPN Keystrokes
Þ$2n Þ$2n
0PM 0PM
12c platinum
ALG Keystrokes
Display Comments
1,445.11
Account balance.
44 Savings
This type of procedure may be continued for any length of time, and may be modified to
meet the user's particular needs.
Savings Account Compounded Daily
This HP 12C Platinum program determines the value of a savings account when interest is
compounded daily, based on a 365 day year. The user is able to calculate the total amount
remaining in the account after a series of transactions on specified dates.
12c platinum / 12C
RPN KEYSTROKES
fs
fCLEARÎ
Þ
$
d
3
6
5
z
¼
d
?0
:$
Þ
t
?2
d
?1
:0
:1
gÒ
n
M
fB
M
\
:$
+
?+3
Compounding Periods Different From
Payment Periods
In financial calculations involving a series of payments equally spaced in time with
periodic compounding, both periods of time are normally equal and coincident. This
assumption is preprogrammed into the HP 12C Platinum.
In savings plans however, money may become available for deposit or investment at a
frequency different from the compounding frequencies offered. The HP 12C Platinum can
easily be used in these calculations. However, because of the assumptions mentioned the
periodic interest rate must be adjusted to correspond to an equivalent rate for the payment
period.
Payments deposited for a partial compounding period will accrue simple interest for the
remainder of the compounding period. This is often the case, but may not be true for all
institutions.
These procedures present solutions for future value, payment amount, and number of
payments. In addition, it should be noted that only annuity due (payments at the beginning
of payment period) calculations are shown since this is the most common in savings plan
calculations.
Savings 47
To calculate the equivalent payment period interest rate, information is entered as follows:
1.
Press g× and press fCLEARG.
RPN Mode:
2.
Key in the annual interest rate (as a percent) and press \.
3.
Key in the number of compounding periods per year and press nz¼.
ALG Mode:
2.
Key in the number of compounding periods per year and press n.
3.
Key in the annual interest rate (as a percent) and press z:n¼.
4.
Key in 1 and press $M.
5. Key in the number of payments (deposits) per year and press
n¼fCLEARG¼.
The interest rate which corresponds to the payment period is now in register "i" and you
are ready to proceed.
Example 1: Solving for future value.
Starting today you make monthly deposits of $25 into an account paying 5% compounded
daily (365-day basis). At the end of 7 years, how much will you receive from the account?
For 8 years you wish to make weekly deposits in a savings account paying 5.5%
compounded quarterly. What amount must you deposit each week to accumulate $6000.
12c platinum / 12C
RPN Keystrokes
g× g×
fCLEARG fCLEARG
5.5\ 4n
4nz¼ 5.5z:n¼
1$M 1$M
52n¼ 52n¼fCLEARG¼fCLEARG¼
8\52§n 8§52n
6000MP 6000MP
Example 3: Solving for number of payment periods.
You can make weekly deposits of $10 in to an account paying 5.25% compounded daily
(365-day basis). How long will it take you to accumulate $1000?
12c platinum
ALG Keystrokes
Display Comments
0.11
-11.49
Equivalent periodic interest
rate.
Periodic payment.
12c platinum / 12C
RPN Keystrokes
g× g×
fCLEARG fCLEARG
5.25\ 365n
365nz¼ 5.25z:n¼
1$M 1$M
52n¼ 52n¼fCLEARG¼fCLEARG¼
10ÞP 10ÞP
1000Mn 1000Mn
12c platinum
ALG Keystrokes
Display Comments
0.10
96.00
Equivalent periodic interest
rate.
Weeks.
Investment Analysis
Lease vs. Purchase
An investment decision frequently encountered is the decision to lease or purchase capital
equipment or buildings. Although a thorough evaluation of a complex acquisition usually
requires the services of a qualified accountant, it is possible to simplify a number of the
assumptions to produce a first approximation.
The following HP 12C Platinum program assumes that the purchase is financed with a
loan and that the loan is made for the term of the lease. The tax advantages of interest
paid, depreciation, and the investment credit which accrues from ownership are compared
to the tax advantage of treating the lease payment as an expense. The resulting cash flows
are discounted to the present at the firm's after-tax cost of capital.
n: Used i: Used PV: Used PMT: Used
FV: 0 R0: Used R1: Used R2: Purch. Adv.
R3: Tax R4: Discount R5: Dep. Value R6: Dep. life
R7: Factor (DB) R8: Used R9: Used R.0: Used
R.1: Used R.2: Used R.3: Unused
Program Instructions:
1. Key in the program.
RPN: - Select the depreciation function and key in at line 26.
ALG: - Select the depreciation function and key in at line 20.
2.
Press g and press fCLEARH.
3. Input the following information for the purchase of the loan:
- Key in the number of years for amortization and press n.
Investment Analysis 51
- Key in the annual interest rate and press ¼.
- Key in the loan amount (purchase price) and press Þ$.
- Press P to find the annual payment.
4.
Key in the marginal effective tax rate
5.
RPN: Key in the discount rate or cost of capital
5.
ALG: Key in the discount rate or cost of capital
6.
Key in the depreciable value and press ?5.
7.
Key in the depreciable life and press ?6.
*
and press ?3.
*
and press \1+?4.
*
and press +1³?4.
8. For declining balance depreciation, key in the depreciation factor (as a percentage)
and press ?7.
9. RPN: Key in the total first lease payment (including any advance payments) and
press \1:3-§?2.
9. ALG: Key in the total first lease payment (including any advance payments) and
press ³1-:3§~³?2.
10. Key in the first year's maintenance expense that would be anticipated if the asset was
owned and press \(³) . If the lease contract does not include maintenance, then
it is not a factor in the lease vs. purchase decision and 0 expense should be used.
11.
Key in the next lease payment and press t. During any year in which a lease
payment does not occur (e.g. the last several payments of an advance payment
contract) use 0 for the payment.
12. Repeat steps 10 and 11 for all maintenance expenses and lease payments over the
term of the analysis.
Optional - If the investment tax credit is taken, key in the amount of the credit after
finishing steps 10 and 11 for the year in which the credit is taken and press
g(043 (ALG:036) t . Continue steps 10 and 11 for the remainder of the
term.
13. RPN: After all the lease payments and expenses have been entered (steps 10 and 11),
key in the lease buy back option and press \1:3-§g(043t. If no
buy back option exists, use the estimated salvage value of the purchased equipment at
the end of the term.
13. ALG: After all the lease payments and expenses have been entered (steps 10 and 11),
key in the lease buy back option and press ³1-
:3§~³g(036t. If no buy back option exists, use the estimated
salvage value of the purchased equipment at the end of the term.
14.
To find the net advantage of owning press :2. A negative value represents a net
lease advantage.
Example: Home Style Bagel Company is evaluating the acquisition of a mixer which can
be leased for $1700 a year with the first and last payments in advance and a $750 buy
back option at the end of 10 years (maintenance is included).
The same equipment could be purchased for $10,000 with a 12% loan amortized over 10
years. Ownership maintenance is estimated to be 2% of the purchase price per year for the
first for years. A major overhaul is predicted for the 5th year at a cost of $1500.
Subsequent yearly maintenance of 3% is estimated for the remainder of the 10 year term.
The company would use sum of the years digits depreciation on a 10 year life with $1500
*
Key in as a decimal (e.g., 5% as .05).
52 Investment Analysis
salvage value. An accountant informs management to take the 10% capital investment tax
credit at the end of the second year and to figure the cash flows at a 48% tax rate. The
after tax cost of capital (discounting rate) is 5 percent.
Because lease payments are made in advance and standard loan payments are made in
arrears the following cash flow schedule is appropriate for a lease with the last payment in
advance.
Year Maintenance Lease Payment Tax Credit Buy Back
8th year.
9th year.
10th year.
Buy back.
After tax buy back
expense.
g(043t g(036t
:2 :2
239.43
-150.49
Present value.
Net lease advantage.
Break-Even Analysis
Break-even analysis is basically a technique for analyzing the relationships among fixed
costs, variable costs, and income. Until the break-even point is reached at the intersection
of the total sales revenue and total cost lines, the producer operates at a loss. After the
break-even point each unit produced and sold makes a profit. Break-even analysis may be
represented as follows.
Profit
Break-even Point
Fixed Costs
Variable
Costs
54 Investment Analysis
The variables are: fixed costs (F), Sales price per unit (P), variable cost per unit (V),
number of units sold (U), and gross profit (GP). One can readily evaluate GP, U or P
given the four other variables. To calculate the break-even volume, simply let the gross
profit equal zero and calculate the number of units sold (U).
To calculate the break-even volume:
RPN Mode:
1.
Key in the fixed costs and press \.
2.
Key in the unit price and press \.
3.
Key in the variable cost per unit and press -.
4.
Press z to calculate the break-even volume.
ALG Mode:
1.
Key in the fixed costs and press ³.
2.
Key in the unit price and press -.
3.
Key in the variable cost per unit and press z.
4.
Press ~~³ to calculate the break-even volume.
To calculate the gross profit at a given volume:
RPN Mode:
1.
Key in the unit price and press \.
2.
Key in the variable cost per unit and press -.
3.
Key in the number of units sold and press §.
4.
Key in the fixed cost and press - to calculate the gross profit.
ALG Mode:
1.
Key in the unit price and press -.
2.
Key in the variable cost per unit and press §.
3.
Key in the number of units sold and press -.
4.
Key in the fixed cost and press ³ to calculate the gross profit.
To calculate the sales volume needed to achieve a specified gross profit:
RPN Mode:
1.
Key in the desired gross profit and press \.
2.
Key in the fixed cost and press +.
3.
Key in sales price per unit and press \.
4.
Key in the variable cost per unit and press -.
5.
Press z to calculate the sales volume.
Investment Analysis 55
ALG Mode:
1.
Key in the desired gross profit and press +.
2.
Key in the fixed cost and press ³.
3.
Key in sales price per unit and press -.
4.
Key in the variable cost per unit and press z.
5.
Press ~~³ to calculate the sales volume.
To calculate the required sales price to achieve a given gross profit at a specified sales
volume:
RPN Mode:
1.
Key in the fixed costs and press \.
2.
Key in the gross desired and press +.
3.
Key in the specified sales volume in units and press z.
4.
Key in the variable cost per unit and press + to calculate the required sales price per
unit.
ALG Mode:
1.
Key in the fixed costs and press +.
2.
Key in the gross desired and press z.
3.
Key in the specified sales volume in units and press +.
4.
Key in the variable cost per unit and press ³ to calculate the required sales price per
unit.
Example 1: The E.Z. Sells company markets textbooks on salesmanship. The fixed cost
involved in setting up to print the books are $12,000. The variable cost per copy,
including printing and marketing the books are $6.75 per copy. The sales price per copy is
$13.00. How many copies must be sold to break even?
12c platinum / 12C
RPN Keystrokes
12000\ 12000³
13\ 13-
6.75-z 6.75z~~³
12c platinum
ALG Keystrokes
Display Comments
12,000.00
13.00
1,920.00
Fixed cost.
Sales price.
Break-even volume.
56 Investment Analysis
Find the gross profit if 2500 units are sold.
12c platinum / 12C
RPN Keystrokes
13\ 13-
6.75- 6.75§
2500§ 250012000- 12000³
If a gross profit of $4500 is desired at a sales volume of 2500 units, what should the sales
price be?
12c platinum / 12C
RPN Keystrokes
12000\ 12000+
4500+ 4500z
2500z 2500+
6.75+ 6.75³
For repeated calculation the following HP 12C Platinum program can be used.
12c platinum
ALG Keystrokes
12c platinum
ALG Keystrokes
Display Comments
13.00
6.25
15,625.00
3,625.00
Sales price.
Profit per unit.
Gross profit.
Display Comments
12,000.00
16,500.00
6.60
13.35
Fixed cost.
Sales price per unit to achieve
desired gross profit.
n: Unused I: Unused PV: Unused PMT: Unused
FV: Unused R0: Unused R1: F R
R3: P R
: U R
4
: GP R
5
: V
2
6-R.6
: Unused
Program Instructions:
1. Key in the program and store the known variables as follows:
a.
b.
c.
d.
e.
Key in the fixed costs, F and press ?1.
Key in the variable costs per unit, V and press ?2.
Key in the unit price, P (if known) and press ?3.
Key in the sales volume, U, in units (if known) and press ?4.
Key in the gross profit, GP, (if known) and press ?5.
2. To calculate the sales volume to achieve a desired gross profit:
a. Store values as shown in 1a, 1b, and 1c.
b.
c.
c.
Key in the desired gross profit (zero for break even) and press ?5.
RPN: Press tg(010t to calculate the required volume.
ALG: Press tg(012t to calculate the required volume.
3. To calculate the gross profit at a given sales volume.
a. Store values as shown in 1a, 1b, 1c, and 1d.
b.
b.
RPN: Press tg(005t to calculate gross profit.
ALG: Press tg(006t to calculate gross profit.
4. To calculate the sales price per unit to achieve a desired gross profit at a specified
sales volume:
a. Store values as shown in 1a, 1b, 1d, and 1e.
b.
b.
RPN: Press g(016t to calculate the required sales price.
ALG: Press g(019t to calculate the required sales price.
58 Investment Analysis
Example 2: A manufacturer of automotive accessories produces rear view mirrors. A new
line of mirrors will require fixed costs of $35,000 to produce. Each mirror has a variable
cost of $8.25. The price of mirrors is tentatively set at $12.50 each. What volume is
needed to break even?
12c platinum / 12C
RPN Keystrokes
35000?1 35000?1
8.25?2 8.25?2
12.5?3 12.5?3
0?5 0?5
tg(010ttg(012t
What would be the gross profit if the price is raised to $14.00 and the sales volume is
10,000 units?
12c platinum
ALG Keystrokes
Display Comments
35,000.00
8.25
12.50
0.00
8,235.29
Fixed cost.
Variable cost.
Sales price.
Break-even volume is between
8,235 and 8,236 units.
12c platinum / 12C
RPN Keystrokes
14?3 14?3
10000?4 10000?4
tg(005ttg(006t
12c platinum
ALG Keystrokes
Display Comments
14.00
10,000.00
22,500.00
Sales price.
F and V are already stored.
Volume.
Gross Profit.
Investment Analysis 59
Operating Leverage
The degree of operating leverage (OL) at a point is defined as the ratio of the percentage
change in net operating income to the percentage change in units sold. The greatest degree
of operating leverage is found near the break-even point where a small change in sales
may produce a very large increase in profits. Likewise, firms with a small degree of
operating leverage are operating farther form the break-even point, and they are relatively
insensitive to changes in sales volume.
The necessary inputs to calculate the degree of operating leverage and fixed costs (F),
sales price per unit (P), variable cost per unit (V) and number of units (U).
The operating leverage may be readily calculated as follows:
RPN Mode:
1.
Key in the sales price per unit and press \.
2.
Key in the variable cost per unit and press -.
3.
Key in the number of units and press §\\.
4.
Key in the fixed cost and press -z to obtain the operating leverage.
ALG Mode:
1.
Key in the sales price per unit and press -.
2.
Key in the variable cost per unit and press §.
3.
Key in the number of units and press ³.
4.
Key in the fixed cost and press àbÞy to obtain the operating leverage.
Example 1: For the data given in example 1 of the Break-Even Analysis section,
calculate the operating leverage at 2000 units and at 5000 units when the sales price is $13
a copy.
12c platinum / 12C
RPN Keystrokes
13\ 13-
6.75- 6.75§
2000§\ 2000³12000
\12000-z
13\ 13-
6.75- 6.75§
5000§\ 5000³12000
\12000-z
12c platinum
ALG Keystrokes
àbÞy
àbÞy
Display Comments
13.00
6.25
25.00
13.00
6.25
1.62
Price per copy.
Profit per copy.
Close to break-even point.
Price per copy.
Profit per copy.
Operating further from the
breakeven point and less
sensitive to changes in sales
volume.
60 Investment Analysis
For repeated calculations the following HP 12C Platinum program can be used:
n: Unused i: Unused PV: Unused PMT: Unused
FV: Unused R0: Unused R1: F R
R3: P R
: Unused
4-R.8
2
: V
Program Instructions:
1. Key in the program.
2. Key in and store input variables F, V and P as described in the Break-Even Analysis
program.
3.
Key in the sales volume and press t to calculate the operating leverage.
4. To calculate a new operating leverage at a different sales volume, key in the new sales
volume and press t.
Example 2: For the figures given in example 2 of the Break-Even Analysis section,
calculate the operating leverage at a sales volume of 9,000 and 20,000 units if the sales
price is $12.50 per unit.
12c platinum / 12C
RPN Keystrokes
35000?1 35000?1
8.25?2 8.25?2
12.5?3 12.5?3
9000t 9000t
12c platinum
ALG Keystrokes
Display Comments
35,000.00
8.25
12.50
11.77
Fixed costs.
Variable cost.
Sales price.
Operating leverage near breakeven.
20000t 20000t
1.70
Operating leverage further
from break-even.
Investment Analysis 61
Profit and Loss Analysis
The HP 12C Platinum may be programmed to perform simplified profit and loss analysis
using the standard profit income formula and can be used as a dynamic simulator to
quickly explore ranges of variables affecting the profitability of a marketing operation.
The program operates with net income return and operating expenses as percentages. Both
percentage figures are based on net sales price.
It may also be used to simulate a company wide income statement by replacing list price
with gross sales and manufacturing cost with cost of goods sold.
Any of the five variables: a) list price, b) discount (as a percentage of list price), c)
manufacturing cost, d) operating expense (as a percentage), e) net profit after tax (as a
percentage) may be calculated if the other four are known.
Since the tax rage varies from company to company, provision is made for inputting your
applicable tax rate. The example problem uses a tax rate of 48%.
12c platinum / 12C
RPN KEYSTROKES
fs
fCLEARÎ
:5
:6
z
:4
+
Þ
:0
+
:0
z
g(000
:3
:1
:2
:0
z
Þ
4. To calculate list price:
a. Do steps 2 and 3b, c, d, e above.
b.
RPN: Press :3tz1g(014tzg(000.
b.
ALG: Press :3t~z~³1g(014t
~z~ ³g(000.
5. To calculate discount:
a. Do steps 2 and 3a, c, d, e above.
b.
RPN: Press :3tg(029t.
b.
ALG: Press :3tg(022t.
6. To calculate manufacturing cost:
a. Do steps 2 and 3a, b, d, e, above.
b.
RPN: Press g(013tg(001t§.
b.
ALG: Press g(013tg(001t§~³.
7. To calculate operating expense:
a. Do steps 2 and 3a, b, c, e, above.
b.
RPN: Press g(012ttg(038t.
b.
ALG: Press g(012ttg(031t.
8. To calculate net profit after tax:
a. Do steps 2 and 3a, b, c, d, above.
b.
RPN: Press g(012ttg(043t.
b.
ALG: Press g(012ttg(039t.
Example: What is the net return on an item that is sold for $11.98, discounted through
distribution an average of 35% and has a manufacturing cost of $2.50? The standard
company operating expense is 32% of net shipping (sales) price and tax rate is 48%.
If manufacturing expenses increase to $3.25, what is the effect on net profit?
12c platinum / 12C
RPN Keystrokes
3.25?3 3.25?3
g(012tt g(012tt
g(043t g(039t
If the manufacturing cost is maintained at $3.25, how high could the overhead (operating
expense) be before the product begins to lose money?
12c platinum
ALG Keystrokes
Display Comments
3.25
58.26
13.66
Manufacturing cost.
Net profit reduced to 13.66%
12c platinum / 12C
RPN Keystrokes
0?5 0?5
g(012tt g(012tt
g(038t g(031t
At 32% operating expense and $3.25 manufacturing cost, what should the list price be to
generate 20% net profit?
12c platinum
ALG Keystrokes
Display Comments
0.00
58.26
58.26
Maximum operating expense
(%).
12c platinum / 12C
RPN Keystrokes
20?5 20?5
:3tz :3t~z~³
1g(014tz 1g(014t~z~³
What reduction in manufacturing cost would achieve the same result without necessitating
an increase in list price above $11.98?
12c platinum
ALG Keystrokes
Display Comments
20.00
11.00
16.93
List price ($).
12c platinum / 12C
RPN Keystrokes
g(013t g(013t
g(001t§ g(001t§~³
12c platinum
ALG Keystrokes
Display Comments
7.79
2.30
Manufacturing cost ($).
Securities and Options
After-Tax Yield
The following HP 12C Platinum program calculates the after-tax yield to maturity of a
bond held for more than one year. The calculation assumes an actual/actual day basis. For
after-tax computations, the interest or coupon payments are considered income, while the
difference between the bond's face value and its purchase price is considered capital gains.
n: Unused i: Yield PV: Used PMT: Used
FV: 0 R0: Used R1: Purchase price R2: Sales price
R3: Coupon rate R4: Capital rate R5: Income rate R6: Used
R7: Used R8-R.5: Unused
Program Instructions:
1. Key in the program.
2.
Key in the purchase price and press ?1.
3.
Key in the sales price and press ?2.
4.
Key in the annual coupon rate (as a percentage) and press ?3.
5.
Key in capital gains tax rate (as a percentage) and press ?4.
6.
Key in the income tax rate (as a percentage) and press ?5.
7.
Press gÕ.
8.
Key in the purchase date (MM.DDYYYY) and press \(³).
9.
Key in the assumed sell date (MM.DDYYYY) and press t to find the after-tax
yield (as a percentage).
10. For the same bond but different date return to step 8.
11. For a new case return to step 2.
Example: You can buy a 7% bond on October 1, 2003 for $70 and expect to sell it in 5
years for $90. What is your net (after-tax) yield over the 5-year period if interim coupon
payments are considered as income, and your tax bracket is 50%?
(One-half of the long term capital gain is taxable at 50%, so the tax on capital gains alone
is 25%)
Purchase price.
Selling price.
Annual coupon rate.
Capital gains tax rate.
Income tax rate.
Purchase Date.
% after tax yield.
Securities and Options 67
Discounted Notes
A note is a written agreement to pay a sum of money plus interest at a certain rate. Notes
do not have periodic coupons, since all interest is paid at maturity.
A discounted note is a note that is purchased below its face value. The following HP 12C
Platinum program finds the price and/or yield
n: Unused i: Unused PV: Unused PMT: Unused
FV: Unused R0: Unused R1: Settl. date R2: Mat. Date
R3: 360 or 360 R4: redemp. Value R5: dis./price R6-R.5: Unused
Program Instructions:
1. Key in the program.
2.
Press gÕ.
3.
Key in the settlement date (MM.DDYYYY) and press ?1.
4.
Key in the maturity date (MM.DDYYYY) and press ?2.
5.
Key in the number of days in a year (360 or 365) and press ?3.
6.
Key in the redemption value per $100 and press ?4.
7. To calculate the purchase price:
a. Key in the discount rate and press ?5.
b. Press t to calculate the purchase price.
c. Press t to calculate the yield.
d. For a new case, go to step 3.
8. To calculate the yield when the price is known:
a. Key in the price and press ?5.
b. RPN: Press g(015t to calculate the yield.
b. ALG: Press g(016t to calculate the yield.
c. For a new case, go to step 3.
Example 1: Calculate the price and yield on this bill: settlement date October 8, 2002;
maturity date March 21, 2003; discount rate 7.80%. Compute on a 360 day basis.
REGISTERS
12c platinum / 12C
RPN Keystrokes
gÕgÕ
10.082002?1 10.082002?1
3.212003?2 3.212003?2
360?3 360?3
100?4 100?4
7.8?5 7.8?5
t t
t t
12c platinum
ALG Keystrokes
Display Comments
10.08
3.21
360.00
100.00
7.80
96.45
8.09
Settlement date.
Maturity date.
360 day basis.
Redemption value per $100.
Discount rate.
Price.
Yield.
Securities and Options 69
Example 2: Determine the yield of this security; settlement date June 25, 2002; maturity
date September 10, 2002; price $99.45; redemption value $101.33. Assume 360 day basis.
12c platinum / 12C
RPN Keystrokes
6.252002?1 6.252002?1
9.102002?2 9.102002?2
360?3 360?3
101.33?4 101.33?4
99.45?5 99.45?5
g(015tg(016t
12c platinum
ALG Keystrokes
Display Comments
6.25
9.10
360.00
101.33
99.45
8.84
Settlement date.
Maturity date.
360 day basis.
Redemption value per $100.
Price.
Yield.
Black-Scholes Formula for Valuing European
Options
This program implements the Black-Scholes formula which has been used extensively in
option markets worldwide since its publication in the early 1970’s. The five inputs are
simply keyed into the five financial variables and then t displays the call option value,
and ~ shows the put option value. The option values produced are accurate to at least
the nearest cent for asset and strike prices under $100.
Reference: Hutchins, 2003, Black-Scholes takes over the HP12C, HPCC (www.hpcc.org)
DataFile,V22,N3 pp13-21.
n: Term to expiry i: Interest rate (%) PV: Stock price PMT: Volatility (%)
FV: Strike price R0: Unused R1: Unused R2: Unused
R3: N(d1) R4: Put value R5: Call value R6: Q·N(d2)
R7-R.9: Unused
Note: The n, i and PMT values must all be based on the same time unit (for example: n is
measured in years or months and i and PMT are rates per year or per month). i is a
continuous percentage rate. PMT is the standard deviation of the continuous percentage
stock return (as observed over the time unit). For sensible output, all inputs should be
positive. The PMT=0 case can be simulated by using a PMT arbitrarily close to 0.
Program Instructions
1. Key in the program.
2. Enter the five inputs into the five financial registers. These values are preserved by the
program.
a. Key in the unexpired term of the option and press n.
b. Key in the risk-free interest rate as a percentage and press ¼.
c. Key in the current (or spot) stock price and press $.
d. Key in the volatility assumption as a percentage and press P.
e. Key in the strike price and press M.
3.
Press R/S. The Call value is displayed. Press ~ to see the Put value.
Example 1: An option has 6 months to run and a strike price of $45. Find Call and Put
values assuming a spot price of $52, return volatility of 20.54% per month and a risk-free
interest rate of ½% per month. Show how to re-scale n, i and PMT to use a yearly time
unit, and how to re-scale them back again to the original monthly basis.
12c platinum / 12C
RPN Keystrokes
6n 6n
.5¼ .5¼
52$ 52$
20.54P 20.54P
45M 45M
t t
~ ~
:gAn :gAn
:gC¼ :gC¼
:P
12gr§P
t t
:ngA :ngA
:¼gC :¼gC
:P
12grzP
The next example is Example 12.7 from Options, Futures, and Other Derivatives (5th
Edition) by John C. Hull (Prentice Hall, 2002).
Example 2: The stock price six months from the expiration of an option is $42, the
exercise price of the option is $40, the risk-free interest rate is 10% per annum, and the
volatility is 20% per annum. Find Call and Put values.
12c platinum / 12C
RPN Keystrokes
.5n .5n
10¼ 10¼
42$ 42$
20P 20P
40M 40M
t t
~ ~
12c platinum
ALG Keystrokes
:P§
12grP
:Pz
12grP
12c platinum
ALG Keystrokes
Display Comments
6.00
0.50
52.00
20.54
45.00
14.22
5.89
0.50
6.00
71.15
14.22
6.00
0.50
20.54
Display Comments
0.50
10.00
42.00
20.00
40.00
4.76
0.81
Time to expiry (months).
Interest rate (% per month).
Stock price.
Volatility (% per month).
Strike price.
Call value.
Put value.
Years to expiry.
Yearly interest rate %.
Yearly volatility %.
Call value (unchanged).
Months to expiry.
Monthly interest rate %.
Monthly volatility %.
Time to expiry (years).
Interest rate (% per year).
Stock price.
Volatility (% per year).
Strike price.
Call value.
Put value.
Forecasting
Simple Moving Average
Moving averages are often useful in recording of forecasting sales figures, expenses or
manufacturing volume. There are many different types of moving average calculations.
An often used, straightforward method of calculation is presented here.
In a moving average a specified number of data points are averaged. When there is a new
piece of input data, the oldest piece of data is discarded to make room for the latest input.
This replacement scheme makes the moving average a valuable tool in following trends.
The fewer the number of data points, the more trend sensitive the average becomes. With
a large number of data points, the average behaves more like a regular average,
responding slowly to new input data.
A simple moving average may be calculated with your HP 12C Platinum as follows.
1.
Press fCLEARH.
2. Key in the first m data points (where m is the number of data points in the average)
and press _ after each entry.
3.
Press gÖ to obtain the first average.
4.
Key in the oldest (first value) entered in step 2 and press g^.
5.
Key in the newest data point (m + 1) and press _.
6.
Press gÖ to obtain the next value of the moving average.
7. Repeat steps 4 through 5 for the remaining data.
Example 1: An electronics sales firm wished to calculate a 3-month moving average for
the dollar volume of components sold each month. Sales for the first six months of this
year were:
January $211,570 April 131,760
February 112,550 May 300,500
March 190,060 June 271,120
n: Unused i: Unused PV: Unused PMT: Unused
FV: Unused R0: m R
R3: X3 R
R7: X7 R
R.1: X11 R
: X4 R
4
: X8 R
8
: X12 R
.2
: X1 R
1
: X5 R
5
: X9 R
9
: Unused
.3-R.4
: X2
2
: X6
6
.0
: X.0
This program can be used for a moving average of 2 to 12 elements. It may be shortened
considerably for moving averages with less than 12 elements. To do this, key in the
program, as shown, from line 01 until you reach a + (ALG: a ? command)
superscripted with the number of elements you desire. Key in this line, then skip the rest
of the program down to line 35. Then key in lines 035 through 039 (ALG:040), being sure
to specify the register number at line 038 (ALG:039), ? m, corresponding to the
number of elements you are using. (For instance, for a 5 element moving average, key in
lines 01 through 13 then go to line 35 in the listing and key in the balance of the program.
Obviously the program listing line 38 (ALG:039), ? m becomes the displayed line 017, ?5 in RPN and 018, ?5 in ALG).
*
At step 038 (ALG:039), m=number of elements in the moving average, i.e. for a 5 element moving
average line 038 (ALG:039) would be ?5 and for a 12 element average line 38 (ALG:039) would
be ?.2
Forecasting 77
Program Instructions:
1. Key in the program.
2.
Press fCLEARH. Key in the number of elements, m, and press ?0.
3.
Key in the first data point and press ?1.
4.
Key in the second data point and press ?2.
5. Continue as above, keying in and storing each data point in its appropriate register
until m data points have been stored.
6.
Press g(000t to calculate the first moving average.
7.
Key in the next data point and press t to calculate the next moving average.
8. Repeat step 7 for each new data point.
Example 2: Calculate the 3-element moving average for the data given in example 1.
Your modified program listing will look like this:
3-month average for May.
3-month average for June.
Seasonal Variation Factors Based on
Centered Moving Averages
Seasonal variation factors are useful concepts in many types of forecasting. There are
several methods of developing seasonal moving averages, on the of more common ways
being to calculate them as a ratio of the periodic value to a centered moving average for
the same period.
For instance, to determine the sales for the 3rd quarter of a given year a centered moving
average for that quarter would be calculated from sales figures from the 1st, 2nd, 3rd and
4th quarters of the year and the 1st quarter of the following year. The seasonal variation
factor for that 3rd quarter would then be the ratio of the actual sales in the 3rd quarter to
the centered moving average for that quarter.
While quarterly seasonal variations are commonly used, the HP 12C Platinum can also be
programmed to calculate monthly seasonal variations using a centered 12 month moving
average. Programs for both of these calculations are represented here:
An HP 12C Platinum program to calculate the quarterly seasonal variations based on a
centered 4-point moving average is:
n: Unused i: Unused PV: Unused PMT: Unused
FV: Unused R0: n R
R3: X3 R
: X4 R
4
: X1 R
1
: X5 R
5
: X2
2
6-R.6
: Unused
Program Instructions:
1. Key in the program.
2.
Press fCLEARH.
3. Key in the quarterly sales figures starting with the first quarter:
a. Key in 1st quarter sales and press ?1.
b. Key in 2nd quarter sales and press ?2.
c. Key in 3rd quarter sales and press ?3.
d. Key in 4th quarter sales and press ?4.
e. Key in the 1st quarter sales for the next year and press ?5.
4.
Press g(000t to calculate the centered moving average for the 3rd quarter of
the first year.
5.
Press t to calculate the seasonal variation for this quarter.
6.
Key in the next quarter's sales and press t to calculate the moving average for the
next quarter.
7.
Press t to calculate the seasonal variation.
8. Repeat steps 6 and 7 for the balance of the data.
80 Forecasting
Example: Econo-Wise Home Appliance Company had quarterly sales for the years 2000
thru 2002 as follows:
n: Unused i: Unused PV: Unused PMT: Unused
FV: Unused R0: n R
R3: X3 R
R7: X7 R
R.1: X11 R
: X4 R
4
: X8 R
8
: X12 R
.2
: X1 R
1
: X5 R
5
: X9 R
9
: X13
.3
: X2
2
: X6
6
: X10
.0
Forecasting 83
Program Instructions:
1. Key in the program.
2.
Press fCLEARH.
3.
Key in 12 and press ?0.
4. Key in the values for the first 13 months, storing them one at a time in registers 1
through .3; i.e.
Key in the 1st month and press ?1.
Key in the 2nd month and press ?2, etc.,
Key in the 10th month and press ?.0, etc.,
Key in the 13th month and press ?.3.
5.
Press g(000t to calculate the centered moving average for the 7th month.
6.
Press t to calculate the seasonal variation for that month.
7.
Key in the value for the next month (14th) and press t to calculate the moving
average for the next month (8th).
8. Repeat steps 6 and 7 for the balance of the data.
These programs may be customized by the user for different types of centered moving
averages. Inspection of the programs will show how they can be modified.
Gompertz Curve Trend Analysis
A useful curve for evaluating sales trends, etc., is the Gompertz curve. This is a "growth"
curve having a general "S" shape and may be used to describe series of data where the
early rate of growth is small, then accelerates for a period of time and then slows again as
the time grows long. The sales curve for many products follow this trend during the
introductory, growth and maturity phases.
The data points to be fit to a Gompertz curve should be equally spaced along the x (or
time) axis and all the data points must be positive. The points are divided serially into 3
groups for data entry.
The following HP 12C Platinum program processes the data, fits it to a Gompertz curve
and calculates estimated values for future data points. The 3 constants which characterize
the curve are available to the user if desired.
n: Unused i: Unused PV: Unused PMT: Unused
FV: Unused R0: Unused R1: S1 R
R3: S3 R
R7: c R
: n R
4
: Unused
8-R.0
: a R
5
: S2
2
: b
6
Program Instructions:
1.
Key in the program and press fCLEARH.
2. Divide the data points to be input into 3 equal consecutive groups. Label them Groups
I, II and III for convenience.
86 Forecasting
3.
Key in the first point of group I and press \(³)
4.
Key in the first point of group II and press \(³).
5.
Key in the first point of group III and press t.
6. Repeat steps 3, 4, and 5 for the balance of the data in each group. After executing step
5 the display shows how many sets of data have been entered.
7.
To fit the data to a Gompertz curve, press g(013t . The resultant display is
the curve constant "a". Constants "b" and "c" may be obtained by pressing :6 and
:7 respectively. The display may need adjusting to see significant digits.
8.
To calculate a projected value, key in the number of the period and press t.
9. Repeat step 8 for each period desired.
Example: The X-presso Company marked a revolutionary new coffee brewing machine
in 1990. Sales grew at a steady pace for several years, then began to slow. The sales
records for the first 9 years of the product's life were as follows.
What are the projected sales volumes for this product in its 10th and 12th year? What is
the maximum yearly sales volume for this product if the present trend continues? What
annual sales rate would the curve have predicted for the 5th year of the product's life?
(Arrange the data as follows:)
a
b
c
Sales in 10th year, (in $K).
Sales in 12th year, (in $K).
Maximum annual sales
(after very long product
life).
Sales in 5th year (actual
sales were $188K).
Forecasting with Exponential Smoothing
A common method for analyzing trends in sales, inventory and securities is the moving
average. Exponential smoothing is a version of the weighted moving average which is
readily adaptable to programmable calculator forecasting.
Exponential smoothing is often used for short term sales and inventory forecasts. Typical
forecast periods are monthly or quarterly. Unlike a moving average, exponential
smoothing does not require a great deal of historical data. However , it should not be used
with data which has more than a moderate amount of up or down trend.
When using exponential smoothing, a smoothing factor is chosen which affects the
sensitivity of the average much the same way as the length of the standard moving
average period. The correspondence between the two techniques can be represented by
the formula:
α
where α is the exponential smoothing factor (with values from 0 to 1) and n is the length
of the standard moving average. As the equation shows, the longer the moving average
period, the smaller the equivalent and the less sensitive the average becomes to
fluctuations in current values.
12+=n
88 Forecasting
Forecasting with exponential smoothing involves selecting the best smoothing factor
based on historical data and then using the factor for updating subsequent data and
forecasting. This procedure uses the following HP 12C Platinum program:
Record for initial values when
month 9 actual figures become
available.
Note: At least 4 periods of current data should be entered before forecasting is attempted.
).
Pricing Calculations
Markup and Margin Calculations
Sales work often involves calculating the various relations between markup, margin,
selling price and costs. Markup is defined as the difference between selling price and cost,
divided by the cost. Margin is defined as the difference between selling price and cost,
divided by selling price. In other words, markup is based on cost and margin is based on
selling price.
The following keystroke sequences are given to readily make these calculations on the
HP 12C Platinum.
CALCULATE GIVEN RPN KEYSTROKES ALG KEYSTROKES
Selling Price Cost & Markup
Selling Price Cost & Margin Key in cost,
Cost Selling Price & Markup Key in selling price,
Cost Selling Price & Margin Key in selling price,
Markup Cost and Selling Price
Markup
Margin
Margin Markup Key in markup,
Margin Key in margin,
Selling Price & Cost Key in selling price,
Key in cost,
key in markup
(in %),
\1\
key in margin (in %),
b-z.
\1\,
key in markup (in %),
b+z.
\,
key in margin
(in %),
Key in cost,
key in selling price,
à.
\\1
~b-z.
\, key in cost,
àÞ.
\\1
~b+z.
\,
b+.
b-.
\,
Key in cost,
key in markup
(in %),
Key in cost,
y-,
key in margin (in %),
b³y.
Key in selling price,
y+,
key in markup (in %),
b³y.
Key in selling price,
-,
key in margin
(in %),
Key in cost,
key in selling price,
à.
Key in margin,
-y
~b³y.
Key in selling price,
³, key in cost,
àÞ.
Key in markup,
+y
~b³y.
+,
b³.
b³.
³,
92
Pricing Calculations 93
Example 1:
If the cost of an item is $160 and the margin is 20%, what is the selling
price? What is the markup?
12c platinum / 12C
RPN Keystrokes
160\1\20 160y-20
b-z b³y
20\\ 20-
1~b-z
Example 2:
If an item sells for $21.00 and has a markup of 50%, what is its cost? What is
12c platinum
ALG Keystrokes
y~b³y
Display Comments
20.
200.00
20.00
25.00
Margin(%).
Selling price.
Margin(%)
Markup (%).
the margin?
12c platinum / 12C
RPN Keystrokes
21\1\50 21y+50
b+z b³y
50\\ 50+
1~b+z
12c platinum
ALG Keystrokes
y~b³y
Display Comments
50.00
14.00
50.00
33.33
Markup (%).
Cost.
Markup(%)
Margin (%).
The following HP 12C Platinum program may be helpful for repetitive calculations of
selling price and costs as well as conversions between markup and margin.
Selling price.
Margin (%).
Cost.
Margin (%).
Markup (%).
Cost.
New markup.
New selling price.
Pricing Calculations 95
Calculations of List and Net prices With
Discounts
It is often useful to be able to quickly calculate a list or net price when the other price and
a series of discount rates are known. Alternatively, if the list and net price and several
discounts are known it may be desirable to calculate a missing discount. The following
series of keystrokes may be used:
RPN Mode:
1.
Key in 1, press
2.
Key in the first discount (as a percentage) and press
3. Repeat step 2 for each of the remaining known discount rates.
4.
To calculate the list price, key in the net price and press
5.
To calculate the net price, key in the list price and press
6. To calculate an unknown discount rate, immediately after step 3 (display should show
1.00), key in the net price, press
7.
Press
:1§z-100§.
ALG Mode:
1.
Key in 1, press
2.
Key in 1
3. Repeat step 2 for each of the remaining known discount rates.
4.
To calculate the list price, key in the net price and press
5.
To calculate the net price, key in the list price and press
6. To calculate an unknown discount rate, immediately after doing step 3 , key in the list
price, press
7.
Press
àÞ.
Example:
rates are 48% and 5%. What is the third discount rate?
The list price of an item is $3.28 and the net price is $1.45. Two of the discount
12c platinum / 12C
RPN Keystrokes
1\\
?1 ?1
48b-?§1 1-48b³?§1
d 5b-?§11-5b³?§1
d1.45\
3.28:1 3.28§:1
§z-100§ ³1.45àÞ
\\?1.
b-?§1d.
:1z.
:1§.
\ and key in the list price.
?1.
-, key in the first discount (as a percentage) and press b³?§1.
z:1³.
§:1³.
§:1³, then key in the net price.
12c platinum
ALG Keystrokes
1
DisplayComments
1.00
0.52
0.95
0.49
10.51
3rd discount rate (%).
96 Pricing Calculations
The following program for the HP 12C Platinum will be helpful in performing the
calculations:
Key in the first discount rate (as a percentage) and press
?1.
t.
4. Repeat step 2 for each of the remaining discount rates.
RPN Mode:
5.
To calculate the list price, key in the net price and press
6.
To calculate the net price, key in the list price and press
7.
To calculate the unknown discount rate, key in the net price, press
price and press
g(007t.
:1z.
:1§.
\, key in the list
Pricing Calculations 97
ALG Mode:
5.
To calculate the list price, key in the net price and press
6.
To calculate the net price, key in the list price and press
7.
To calculate the unknown discount rate, key in the net price, press
price and press
Example: Calculate the unknown discount rate for the previous example. If the list price
is now raised to $3.75 what is the new net price?
g(008t.
z:1³.
§:1³.
³, key in the list
12c platinum / 12C
RPN Keystrokes
1?1 1?1
48t 48t
5t 5t
1.45\ 1.45³
3.28g(007t 3.28g(008ttt
3.75:1§ 3.75§:1³
12c platinum
ALG Keystrokes
Display Comments
1.00
0.52
0.95
10.51
0.89
1.66
3rd discount rate (%).
Include 3rd discount rate in
calculation.
New net price.
Statistics
Curve Fitting
Exponential Curve Fit
Using the ° function of the HP 12C Platinum, a least squares exponential curve fit may
be easily calculated according to the equation y=Ae
technique is often used to determine the growth rate of a variable such as a stock's value
over time, when it is suspected that the performance is non-linear. The value for B is the
decimal value of the continuous growth rate. For instance, assume after keying in several
end-of-month price quotes for a particular stock it is determined that the value of B is
0.10. This means that over the measured growth period the stock has experienced a 10%
continuous growth rate.
If B>0, you will have a growth curve. If B<0, you will have a decay curve.
Examples of these are given below.
Bx
. The exponential curve fitting
GROWTH CURVE
(B>0)
Quantity
Time
The procedure is as follows:
1.
2.
3.
98
fCLEARH .
Press
For each input pair of values, key in the y-value and press
corresponding x-value and press
After all data pairs are input, press
(between ln y and x).
_ .
Quantity
gR~ to obtain the correlation coefficient
DECAY CURVE
(B<0)
Time
g°, key in the
Statistics 99
4.
Press 1
gRg>0gRg> to obtain A in the equation above.
RPN Mode:
5.
Press
~dzg° to obtain B.
6.
Press
g>1- to obtain the effective growth rate (as a decimal).
ALG Mode:
5.
Press
z~d³g° to obtain B.
6.
Press
g>-1³ to obtain the effective growth rate (as a decimal).
7.
To make a y-estimate, key in the x-value and press
Example 1: A stock's price in history is listed below. What effective growth rate does this
represent? If the stock continues this growth rate, what is the price projected to be at the
end of 2004 (year 7)?
First data pair input.
Second data pair input.
Third data pair input.
Fourth data pair input.
Fifth data pair input.
Sixth data pair input.
Correlation coefficient
(between ln y and x).
A
B
Effective growth rate.
Projected price at end of year
7 (2004).
100 Statistics
For repeated use of this routine, the following HP 12C Platinum program will be useful.