I have raw data that runs about 55,000 rows in excel (without going into why,
we'd like to keep our formulas in excel as opposed to Access) with maybe
20-30 columns. We then have a summary sheet which uses many sumproducts to
lookup on the data and return results base on criteria which we have
successfully done.

The problem is the spreadsheet crashes excel because the many sumproducts
combined with so many rows needs so much power (at least that's is what
appears to be the cause).

I thought about separating the summary spreadsheet into pieces but I'd like
to avoid making it unmanageable. I was told that DSUM is as much as 50%
faster than sumproduct, but I hate DSUM, and, in our case, that would still
need 6 hours of computation time.

Any magic bullets out there for spreadsheet design (workspaces, other lookup
with category functions, or other methodology with existing functions) that
can substantially reduce calculation time?

tia,
Dave