Section 4: Additional Financial Functions  81 
 
File name: HP 12c Pt Converted_user's guide_English_HDP0F123E02_080207  Page: 11 of 281   
Printed Date:  {  2007/8/2Dimension: 14.8 cm x 21 cm 
 
Note: If you change the number in the n register in order to change an N
j
, 
be sure to reset the number in the n register to the total number of cash flow 
amounts originally entered (not including the amount of the initial investment 
CF
0
). If this is not done, NPV and IRR calculations will give incorrect results. 
Example 1: 
With the cash flows now stored in the calculator, change CF
2
 from 
$11,000 to $9,000, then calculate the new NPV for a 13.5% return. 
Keystrokes Display  
9000
?
2 
9,000.00 
Stores the new CF
2
 in R
2
. 
13.5
¼
 
13.50 
Stores i. 
*
 
fl
 
–644.75 
The new NPV. 
Since this NPV is negative, the investment would decrease the financial value of 
the investor’s assets. 
Example 2:
 Change N
5
 from 2 to 4, then calculate the new NPV. 
Keystrokes   Display   
5
n
 
5.00 
Stores j in the n register. 
4
ga
 
4.00 
Stores the new N
5
. 
7
n
 
7.00 
Resets the number in the n register 
to its original value. 
fl
 
–1,857.21 
The new NPV. 
 
*
 This step is necessary in this example because we have calculated IRR since the first time we 
calculated NPV. The IRR calculation replaced the 13.5 we keyed into i before calculating 
NPV with the result for IRR – 13.72.