Hi. I have a formula that is summing items in several worksheets. The
formula is:

=SUM('A:R'!D54)

The value that this formula shows is zero even though there is data in the
other cells. If I enter into this cell (by pressing F2) and do nothing more
than press the enter key, the value changes to correctly sum up the values.

Does anyone understand why this is occurring? Recalculation is set to
Automatic and pressing F9 does not fix this.

I have this formula replicated in about 1,000 locations throughout this
workbook.

Thanks,
Mike.