Perhaps give this a try as well ..

With EOM real dates as col headers assumed in B1:AU1, data in row2 down

Let's assume EOM date inputs for the desired start-end period will be
specified within AW1:AX1 (say), for eg: AW contains: 31-Mar-06, AX1 contains:
31-May-06

Then placed in AV2:
=IF(OR($AW$1="",$AX$1=""),"",SUM(OFFSET(A2,,MATCH( $AW$1,$B$1:$AU$1,0),,MATCH($AX$1,$B$1:$AU$1,0)-MATCH($AW$1,$B$1:$AU$1,0)+1)))
Copy AV2 down as far as required

Col AV should return the desired results ..
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
---
"TomCat" wrote:
I also forgot to mention that this project spans over several years and has
133 rows below the header line, which contains the dates.

Dates 31-mar-06 30-apr-06 31-may-06 30-jun-06 out to end dec
09
Task 1 5.5 3.4 1.2 2.6
Task 2 2.1 5.5 4.3 2.5
etc....down