create a rolling sum??
How about
=SUMIF(A4:A17,""&D1,B4:B17)
where A4:A17 contain the dates, D1 contains the date 30/60/90 days ago and
B4:B17 contain the data you want to sum.
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Hope this helps,
MarkN
"dustin" wrote:
I need to create a rolling sum always taking the last 30 entries(cells) and
adding them up. Basically to keep an accurate "last 30/60/90 days sum" is
there a formula to do this?? using dates or just cells?
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