Lookup/offset functions

Hello.

I've a problem. I've a workbook with 52 sheet (each representing a week in 2010), and in every sheet is a 19x21 matrix which contains data from 21 clients and 19 tasks. I have made a 21 other sheets which sum up every client’s tasks in one sheet in order to do some statistics.

I've tried some solutions with the different lookup functions, but I got a lot of errors, so now I think I’ll use the offset function, since the data that need to be replicated always have the same location.

But with 52 weeks, and 19 clients I’ve to change the function almost 1000 time, so my question is now - do anybody know a smarter solution?