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Nigel[_2_] Nigel[_2_] is offline
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Default Checking if the sum of a percentage is equal to one

floating point arithmetic is the issue -- take a look here

http://support.microsoft.com/kb/78113


--

Regards,
Nigel




"PSmith" wrote in message
...
Have a bit of a problem here.

Here's a sample sheet where I have reproduced my problem:
http://pbsmith.iweb.bsu.edu/percentageSum.xls (you will need have macros
enabled, as this is a VBA subroutine)

I have 2 columns, where the individual percentages are added together. I
have a "Grand total" which adds up the individual totals. I do a check
against the grand total to make sure it's equal to one (using .Range() <
1)

The problem is if there are 10 values of 10%, this check fails.

If you replace one of the 10% values with two 5% values, the check
succeeds
(as it should, as long as it still adds up to 100%).

I'm using Excel 2007. Any feedback on this problem would be greatly
appreciated; I'm at a bit of a loss myself.