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Re: identifying percentile range to perform averages
I've tried to build a small version of the workbook, with 900 scores in a column, split among four graders.
If the 900 were a constant number, I could find the results by using =average(a2:a10) through =average(a893:a901). But the 900 is not a constant but is continually growing (the real collection is over 6400 and gains about 100 new scores every day and will do so for a number of weeks).
So I'm looking for a formula that will allow me to find the average of the first 1.0% of all scores, the second 1.0% of all scores, the third 1.0% of all scores, et cetera.
In the sample workbook I've only added averages through the 12th 1.0% range. (And don't know if this matters, but this sample was created at home in 2007 but at work the original is in 2003).
EDIT: Since I mentioned wanting to look at smaller subsets, I added one for Grader a, but I realize that it would be best to deal with one question at a time - so for the moment ignore the subset to the right within the workbook.
Last edited by wilshire; 06-25-2009 at 01:18 AM.
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