Compiling weekly numbers from same column, cross referencing serial numbers,zones, tasks and dates in other columns.

[Sosborg]

Hi,

I've built a barcode scanning system to keep track of what files and boxes are being worked on through the process.
I use VBA and in cell formulas and the database is just an excel table.

I need to do a weekly summary of how much progress has been done daily (the difference between the two values in one column), cross-referenced and divided between"Task" and "Zone".

I hope the attached screenshot explains what I am after.
Using VBA would be the best, as the sheet contains thousands of rows. I have the following formula in the cell that works but it makes the entire computer crash. (I'm working in a non-profit and our computers are 8 years old). Disregard the cell and column references in the formula below, they were from the sample sheet, not the real sheet. In the screenshot, you find the actual columns used.

=IFERROR(ABS(@INDEX(Sheet2!$AF:$AF,AGGREGATE(14,6,ROW(Sheet2!$AG$2:$AG$58)/((INT(Sheet2!$AG$2:$AG$58)=INDEX(OFFSET($C$6:$BF$6,8*(INT((ROWS($C$6:$C14)-1)/8)),0),1+4*INT((COLUMNS($C16:D16)-1)/4)))*(Sheet2!$AH$2:$AH$58=$B16)*(Sheet2!$AI$2:$AI$58=D$7)),1))-@INDEX(Sheet2!$AF:$AF,AGGREGATE(15,6,ROW(Sheet2!$AG$2:$AG$58)/((INT(Sheet2!$AG$2:$AG$58)=INDEX(OFFSET($C$6:$BF$6,8*(INT((ROWS($C$6:$C14)-1)/8)),0),1+4*INT((COLUMNS($C16:D16)-1)/4)))*(Sheet2!$AH$2:$AH$58=$B16)*(Sheet2!$AI$2:$AI$58=D$7)),1)))/100,"")

Is it possible at all to do this through VBA ? Or to make the formula in-cell less demanding?

Any comment, suggestion or question would be appreciated. Hope I've made it clear enough to understand.