You could count the number = .9 and subtract the ones 1.10
=countif(a1:a10,"=.9") - countif(a1:a10,"1.1")

Or you could count the ones that are trapped between those numbers:
=SUMPRODUCT(--(A1:A10=0.9),--(A1:A10<1.1))

=sumproduct() likes to work with numbers. The -- converts trues and falses to
1's and 0's.





KG wrote:

For a range of cells containing percentages, how can I use COUNTIF to count
those cells whose values fall between 90% and 110% ?

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Dave Peterson