I have data from different worksheet according to the week number. I am using
If function to look for the data for over different worksheet. My problem is
every week there will be a new weeksheet and I have to edit the code to
include the new week. Is there a simplier solution? Thanks.

=IF(SUMIF('[Daily Output (2006).xls]Week14'!$F:$F,B4,'[Daily Output
(2006).xls]Week14'!$J:$J),SUMIF('[Daily Output
(2006).xls]Week14'!$F:$F,B4,'[Daily Output
(2006).xls]Week14'!$J:$J),IF(SUMIF('[Daily Output
(2006).xls]Week15'!$F:$F,B4,'[Daily Output
(2006).xls]Week15'!$J:$J),SUMIF('[Daily Output
(2006).xls]Week15'!$F:$F,B4,'[Daily Output
(2006).xls]Week15'!$J:$J),IF(SUMIF('[Daily Output
(2006).xls]Week16'!$F:$F,B4,'[Daily Output
(2006).xls]Week16'!$J:$J),SUMIF('[Daily Output
(2006).xls]Week16'!$F:$F,B4,'[Daily Output
(2006).xls]Week16'!$J:$J),SUMIF('[Daily Output
(2006).xls]Week17'!$E:$E,B4,'[Daily Output (2006).xls]Week17'!$I:$I))))