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14b is not calculating PMT correctly. I have a 14B 50th Aniv Edition. I am a mortgage professional, so, I calculate PMT quite a bit. It has suddenly started calculating PMT incorrectly. I have checked it against several sources. Any ideas why? Is there a setting that got messed up? Thanks in advance!

Did you try again after a reset of the calc?

Not a finance guy, but doesn't the PMT depend on the payment schedule.

That is, is there a flag that toggles Canadian to American style, another that calculates end of payment period or beginning?

In other words, if it worked correctly out of the box, then try the reset suggested as this would reset all the applicable states.


I'm not sure how to reset it. I took the batteries out for 10 minutes and that did not fix it.

I found instructions online on how to reset it. It did not help.

I agree, this may be part of the problem. But I do not have the instructions....

I was desperate with the same problem with my 12c - I wasn't able to reproduce my mortgage numbers froim the bank. At the end it was all about being in BEG mode instead of END!

In other models it may have to do with the number of oeriods per year.

Yeah, for loans you want to be in END mode. You will get the wrong payment amount if you are in BEGIN mode.

and that will help us see if the 14b is giving wrong answers. If so, it is always possible it has bit the dust.

But easier to tell if you give very complete examples. :-)

Almost all the problems I've had like this ended up being the P/YR setting was off.

This happens on the HP10b as well.

Press RCL SHIFT PMT and you should get P/YR=12.00
You can change to 26 Payments per yr by typing 26 STO SHIFT PMT

If you hold ON+N+SIGMA at the same time, The P/YR will get reset to 12.

If this does not work, type here your 5 FIN variables so we can recreate the issue.

E.g. ( I=4%, PMT=360, PV=1000, FV=0 ----> PMT= -4.77 )


The ON+N+SIGMA worked! Somehow, the darn thing got set to 10 payments a year. I'm not sure how, since it just sits on my desk, not banged around a bag or anything. Thanks!!!!

I don't have a 14B but on my ancient 10B, when you clear the TVM registers using the [SHIFT] CLEAR_ALL sequence, it briefly displays the P_Yr value.

Do you never clear your TVM registers?

(It could be that this clears EVERYTHING on this machine. I am not sure. I bought it as a red-shirted "expendable crew member" so I could learn how to dismantle Pioneer calculators. Don't use it very much -- much prefer my (several) 17Bii's running in RPN mode!)