I have an excel 2007 file with worksheets for each month. The Feb-Dec sheets
each have cells that contain the formula "=B25+PrevSheet(F25)" to accumulate
the sum of corresponding cells of earlier month worksheets using a function
"PrevSheet(x)" that I wrote to pick up the specified cell value from the
previous month worksheet. Each worksheet has a fairly large number of cells
that use this formula.

When I make changes in earlier month sheets the following month sheets do
not automatically update their cumulative values. Clicking Recalculate does
not perform and update either. The only way I seem to be able to update
these cum cells is to select each one, click up in the formula bar and then
press enter. This is a very tedious process.

How can I get the cells to update automatically?

Thank you for your help, John