You want to answer the question: If I invest $97.50, what interest rate gets me
to $100.00 in 20 days? The rate function will do this for you:

=rate(20/365,0,-97.50,100.00)

The answer is 58.73%.

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Regards,
Fred


"tiger1969" wrote in
message ...

How do you write a formula that calculates the Annual Percentage
Interest Cost of the Discount not taken for any set of data.

Annual Percentage Interest Cost of Discount Not Taken

Prompt Payment Discount Amount 2.5%

Invoice has to be paid within how many days to qualify for the discount
10
Net amount of invoice to be paid within how many days 30

Annual Percentage Interest Cost of Discount Not Taken

Please help

Grahame


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tiger1969
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