6 Replies Latest reply on May 2, 2014 4:20 AM by JudeAshton

# How to do Compound interest calculations in FMP?

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How to do Compound interest calculations in FMP?

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Hi there,

I am using FMPro 13 on Apple Mac. I have Excel that uses a formula

=FV(Appendix!B3,'Personal Details'!B39,0,-B4,0)

While I know it references other sheets, I am trying to recreate the formula in FMPro. We have data in the database it references.

I have tried to do the FV command, but we are struggling trying to get it to do the compound interest. Any ideas?

• ###### 1. Re: How to do Compound interest calculations in FMP?

You might want to look at some custom functions:

http://www.briandunning.com/filemaker-custom-functions/results.php

• ###### 2. Re: How to do Compound interest calculations in FMP?

If you can look up the actual algebra used to compute FV in Excel, we can show you how to set up an equivalent calculation in FileMaker--which could be set up as a custom function, but if this works as I vaguely recall, it won't have to be a custom function.

There is an FV function in FileMaker: FV(payment; interestRate; periods)

How does it differ from the Excel version?

• ###### 3. Re: How to do Compound interest calculations in FMP?

The algebra in Excel is FV(rate,nper,pmt,pv,type)

Filemaker is FV ( payment ; interestRate ; periods )

So if anything Excel has more options on there. I have a figure that excel is getting. But we cant recreate the figure with the FV formula on filemaker.

The Excel formula is we need to workout for filemaker is:-

=FV 2.5%,10, 0, -2000, 0

In Excel 0, is doing the compound interest. But when I do that in Filemaker we dont get the result.

The result should be:- £2,560.17

• ###### 4. Re: How to do Compound interest calculations in FMP?

The algebra in Excel is FV(rate,nper,pmt,pv,type)

That's not what I'm looking for. That just lists the parameters. The "algebra" is the actual mathematical formula used. This can usually be found in a an applications help file. When I look up FV in FileMaker, I can find the formula that it uses. I've uploaded it as a screen capture from the help file here in this post. If we can put the two formulae side by side, we may be able to derive one that computes what you need--either as a simple calculation or in a custom function. And you can also use that info to search the Brian Dunning web site for a custom function that does this computation as Steve Martino suggested.

• ###### 5. Re: How to do Compound interest calculations in FMP?

FV = P(1+r/n)^(Y*n)

I think the above is what Excel does.

• ###### 6. Re: How to do Compound interest calculations in FMP?

Okay, we resolved the formula.

2000*(1+.025)^10

2000 is the payment or you can point it to a total, 0.25 is the interest rate and 10 is year to retirement.

Thanks for everyones help.