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Hi
I'm using a COUNTIFS formula to count the number of rows between two dates, according to a number of additional criteria, as per the example in this article, but I just can't get it to return anything other than zero. The data is being pulled from SQL, and I have verified that the result should be 14, not 0. I'm already using COUNTIFS for other portions of my report, with success, but now need to incorporate a date range.

The formula:
=COUNTIFS(Data!C:C,">="&K3,Data!C:C,"="&K4,Data!L:L,"Atherstone",Data!T:T,"Service",Data!AA:AA,"Verbal")

K3 is the start date, K4 is the end date.
Data! is the sheet that has all the data on it - Sheet1 holds the report (and the start/end dates). I'm pretty sure that I'm pulling date data through correctly (i.e. not converted to varchar or anything like that), but it's the last part of a very large report and I'm getting bogged down, not to say more than a tad frustrated...
Any advice? Gotchas?