Sum,

[Steve]

Hello. In sheet1, cells A1:A3, I have 3 dates. In sheet 2, across
row 2 I have lots of dates. In column AA, I would like to write a sum
formula that will sum the 3 cells that match the dates in Sheet!
A1:A3. And then be able to copy that formula down on Sheet2.
Possible? Thanks!!

 

[Max]

In Sheet2,

Assume col header dates are within A2:E2,
with data to be summed starting in row3 down

Put in AA3:
=SUMPRODUCT(--ISNUMBER(MATCH($A$2:$E$2,Sheet1!$A$1:$A$3,0)),A3:E3)
Copy down. Adapt the ranges to suit your actual