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Old October 3rd, 2005, 08:05 PM
David Billigmeier
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It is because the denominators (the salaries in column A) of the fractions
being added (when you average the percent column) aren't all the same.
Remember back to fraction addition:

7/4 + 8/2 DOES NOT equal 15/6... but instead 8/2 = 16/4, and so 7/4+16/4 =
23/4.

--
Regards,
Dave


"Robin Blackwell" wrote:

Hi all,

I have an Excel function query that's really bugging me. In column "A" I
have about 80 staff annual salaries. In column "B" I have their
corresponding annual salary increase.

If I sum Column "A", and sum Column "B", and divide the resultant totals, I
get what I assume to be the average annual salary increase for the group
(3.46%).

However, if in Column "C" I calculate each individual's average annual
increase (B2/A2 etc), and then use the AVERAGE function over all of the
results in column "C" I get a different answer (3.79%).

Why is this please, and which answer is correct?

Thanks,

Robin