add numbers based on date reference

[elements]

hi everybody!

i need your help for a smal problem.

i have a column with dates and a column with coresponding numbers. i want to add the numbers, whose coresponding date is less or equal to a certain date.
i`ve tried sumif, but no succes.
any ideas?

[sweep]

How about something along these lines

=SUMIF(A1:A30,">"&DATEVALUE("18/1/2010"),B1:B30)

This will return a sum of values in B1:B30 where the date in A1:A30 is after 18/1/2010

[BigDat6CC]

You might consider using the SUMPRODUCT function

[elements]

works like a charm sweep, except for one little thing. i want that my formula updates the date with the curent date. i`ve tried replacing "DATEVALUE("18/1/2010")" with today() function, but it says: volatine.

[sweep]

This works for me:

=SUMIF(A1:A30,">"&TODAY(),B1:B30)

is that what you have?

[sweep]

Just a note regarding SUMPRODUCT:

=SUMPRODUCT((A1:A30>DATEVALUE("18/1/2010"))*(B1:B30))

You could use it, but, it is an array formula, and therefore more resource hungry (and therefore slower) than the SUMIF.

[elements]

now it works. i was missing someting.
thanks a lot sweep and BigDat6CC!