# Mortgage Constant (Rm) Formula for the HP19BII

And another program for the HP 19BII:

To Program the Mortgage Constant (Rm) Formula:

1. Press the ON key.

2. Press the key under the “SOLVE” prompt.

3. Find a blank row using the down arrow key and type the following formula exactly as it appears here:

(Remember not to add any spaces, and all of the 0’s after “MORTGAGE. CONSTANT” are zero’s. The lower case “x” is a multiplication sign, not the letter “x”.)

MORTGAGE.CONSTANT:(-12
)x(PMT((TERMx12):I%YR:1
:0:12:0))=RM

To Use the Mortgage Constant (Rm) Program:

4. Press the key under the “CALC” prompt. If you have entered the program correctly, a new row of prompts will appear:“TERM”, “I%YR”, and “RM”. (If not, you need to debug. Check your input for mistakes and make corrections. Then press the “CALC” key again to test the formula.)

5. Now (if you see the prompts listed above) just type each input then press the key under the appropriate prompt. Finish by pressing the key under the “RM” prompt. The calculator will return the correctly calculated Mortgage Constant (Rm).

Try this Example:

Type:15 (15 year term). Press the key under:TERM
Type:9 (9% interest). Press the key under:I%YR
Solve for Rm. Press the key under:RM

Your answer for Rm should be .1217 (Set DISP to 4 digits).