HP 12C Programming III: Refinancing, Advance Payments in a Lease, NPV, NFV, NUS
HP 12C Programming Part I: Modulus, GCD,
PITI
HP 12C Programming Part
II: Weekday Number, Gross Up Calculation
HP 12C Refinancing: When refinancing “resets” the clock.
Sometimes when a long
term mortgage is refinanced, the original length of term is reset. We will assume payments are made monthly.
Input:
Store the following amounts
in the registers:
Clear the TVM variables
by pressing [ f ] [x<>y] (CLEAR FIN)
Original number of
payments, [ n ]
Annual rate, [ 12÷ ] [ I
]
Loan Amount, [ PV ]
Number of payments that
have been made prior to refinance, [STO] [ 0 ]
(R0)
New annual rate,
[ENTER], 12, [ ÷ ], [STO] [ 1 ] (R1)
Run the program by
pressing [R/S]. The original payment is
calculated. Press [R/S] again to get the
balance. Enter any additional monies
(can be $0.00) received due to the refinance.
Finally, press [R/S] again, and the new payment is calculated.
Program:
STEP

CODE

KEY

01

45, 11

RCL n

02

44, 2

STO 2

03

14

PMT

04

14

PMT \\ calculate payment

05

31

R/S

06

45, 0

RCL 0

07

11

n

08

15

FV

09

31

R/S \\ calculate balance, ask for amount of
withdrawn

10

30



11

16

CHS

12

13

PV

13

0

0

14

15

FV

15

45, 1

RCL 1

16

12

i

17

45, 2

RCL 2

18

11

n

19

14

PMT

20

43, 33, 00

GTO 00

Example:
A couple purchased a
house for $185,000. The mortgage lasts
for 30 years (360 months) with a 4.8% interest rate (0.4% periodic rate). 180 payments have passed, and the couple is
able to refinance the mortgage (but pay that amount in 30 years) at a rate of
3.84%. $15,000 is also cashed out.
Input:
360 [ n ]
0.4 [ i ]
185000 [PV]
180 [STO] [ 0 ]
0.32 [STO] [ 1 ]
Results:
[R/S] 970.63
(The original payment is $970.63)
[R/S] 124,373.78 (Balance of $124,373.78)
Enter 15000, press
[R/S] 652.60 (New payment is $652.60)
HP 12C: Advance
Payments in a Lease
The program calculates
the payment where you pay number of payments in advance.
Formula:
PMT = (PV – FV*(SPPV(I%/12:N)))
÷ (UPSV(I%/12:NADV)+ADV)
Where:
SPPV: present value of $1, where FV is equal to 1
USPV: present value of $1, where PMT is equal to 1
Input:
Number of payments, [
STO ] [ 0 ]
Number of payments made
in advance, [ STO ] [ 1 ]
Periodic Rate, [STO] [
2 ]
Price of the Lease,
[STO] [ 3 ]
Salvage Value, [ STO ]
[ 4 ]
Calculate lease payment
by pressing [R/S].
STEP

CODE

KEY

01

42, 34

Clear FIN ([ f ] [x<>y])

02

1

1

03

16

CHS

04

15

FV

05

45, 2

RCL 2

06

12

i

07

45, 0

RCL 0

08

11

n

09

13

PV

10

45, 4

RCL 4

11

20

*

12

16

CHS

13

45, 3

RCL 3

14

30



15

45, 11

RCL n

16

45, 1

RCL 1

17

30



18

11

n

19

45, 15

RCL FV

20

14

PMT

21

0

0

22

15

FV

23

13

PV

24

45, 1

RCL 1

25

40

+

26

10

÷

27

43, 33, 00

GTO 00

Example:
A machine with a cost
of $40,000.00 is leased for 48 months.
Two advanced payments are required.
Interest rate is 10% (monthly periodic rate is 10%/12). The residual value is estimated to be $15,000.
Input:
48 [STO] [ 0 ] \\ term
2 [STO] [ 1 ] \\ 2 advanced payments
10 [ENTER] 12 [ ÷ ]
[STO] [ 2 ] \\ interest rate
40000 [STO] [ 3 ] \\ cost
15000 [STO] [ 4 ] \\
salvage value
Result:
[R/S] 1249.30
(Each payment is $1,249.30. Two
advanced payments are $2,498.60).
Source: HP 17bII+ Financial Calculator User’s
Guide. Hewlett Packard. Edition 3:
2007
HP 12C: Net Present Value, Net Future Value, Net
Utility Stream
Input:
Clear the registers/finance
registers
Press [ g ] (GTO) 00 to
get the pointer to line 00. (000 for the
HP 12C Platinum editions. Remember, the
Platinum editions have up to 400 steps and line numbers are in triple digits)
Store 1 in [ n ] (don’t
worry, n is incremented in the main loop)
Store periodic interest
rate in [ i ].
Store 0 in register
0 (0 [STO] [ 0 ]). Register 0 is use for calculating NPV
Enter each cash flow
one at a time, and press [R/S].
Ready to calculate:
Press [ g ] (GTO)
10 (or 010) to get the pointer to line
10.
Press [R/S] to get NPV
(net present value)
Press [R/S] to get NFV
(net future value)
Press [R/S] to get NUS
(net utility stream)
Program:
STEP

CODE

KEY

01

16

CHS // main loop: input data

02

15

FV

03

45, 11

RCL n

04

1

1

05

40

+

06

11

n

07

13

PV

08

44, 40, 0

STO+ 0

09

43, 33, 0

GTO 00 // finish main loop

10

45, 0

RCL 0 // calculation part

11

31

R/S // net present value

12

1

1

13

16

CHS

14

13

PV

15

0

0

16

14

PMT

17

15

FV

18

45, 0

RCL 0

19

20

*

20

31

R/S // net future value

21

45, 0

RCL 0

22

1

1

23

16

CHS

24

14

PMT

25

0

0

26

15

FV

27

13

PV

28

10

÷

29

31

R/S // net utility stream

Example:
Rate: 15%
Cash Flow #

Flow

0

10,000.00

1

2500.00

2

3500.00

3

5000.00

4

5000.00

Input:
[ f ] CLEAR FIN, [ f ]
CLEAR PRGM
1 [ n ] // do this on each new problem
0 [STO] [ 0 ] // do this on each new problem
15 [ i ]
10000 [CHS] [R/S]
2500 [R/S]
3500 [R/S]
5000 [R/S]
5000 [R/S]
Results:
[GTO] 10 [R/S]:
NPV = 966.76
[R/S]: NFV = 1690.88
[R/S]: NUS = 338.62
Input slowly and
carefully.
This blog entry is
property of Edward Shore, 2016.