In what could be read as a bit of a dig at Excel, Apple publishes a technote containing a comparison between the number of populated cells in a Numbers spreadsheet file and the number of populated cells in an Excel file for the same amount of memory (hint, for > 1Gb of memory, Numbers can handle 1.5 million or more, Excel can handle 300,647 or more. Not that that says much really.
Are you talking about RAM?
Are we comparing Mac Excel to Numbers?
I suspect the results would be very strongly skewed by Rosetta.