I have a workbook with a varying number of worksheets.

Each sheet has a "sheet total" cell that sums a range
of "quantity" cells. The first worksheet has a "project
total", which will contain the sum ot the sheet totals for
the entire workbook. I have the function for that task.

I'd like the "project total" function (macro) to run
whenever any of the "sheet total" values change.

how do I associate the macro to that event?

Thanks in advance,
Rich