TVM and example in User Guide

[salvomic]

(05-16-2015 10:43 PM)kharpster Wrote:  Salvo,

You are correct sir, I did the same exercise as you and it looks like a group's principal and interest amounts are now only for a given group. Whereas in the previous firmware (verified with my Android emulator), they were accumulative amounts. An argument can be made to display it either way, but, I think it would be best to have the option to display it both ways with maybe a checkbox to select the desired format...

hi,
yes, I think they now have uniformed the method of calc to that in the HP 12C.
In 12C I get result like mine giving i/12=6.5, n=0, PV=150000, FV=0, PMT=-948.10, with minus sign (important) (this can be solved in the Prime, or calculating by 12C putting n*12=30, that's n=360); then using 12, f+Amort I get the value for interest, with x<>y that for principal, with RCT PV the residual amount, and so on giving again 12 f+Amort...
So the result now is equal to that in the 12C, giving 12 as 12 is an year (12 months)...

Yes, I think that, a part of the choose for Group Size, it would be interesting to have also a choose for grouped or accumulative list...

I would like much to have also a complete Cash Flow routine in the Prime, like that in the 12C, I hope to test a program.
For now there is NPV (from Eddie Shore), that calculates Net Present Value; it would be nice to add also an IRR (Internal Rate of Return) function to it...

Salvo