Hi Dave,

How could we possibly say without knowing your formulas?
In general, large files/numbers of computations shouldn't make Excel crash (whatever you mean with "crash").

Post again with examples of your formulas, the version of Excel, memory and processor specs and what you see when Excel crashes.

In the meantime, check

www.decisionmodels.com

for many tips on speed and capacity problems.

--
Kind regards,

Niek Otten
Microsoft MVP - Excel


"Dave Breitenbach" wrote in message
...
|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