I have a spreadsheet that takes up about 30 meg (Why? it has only 1500 rows and a dozen columns with much less than 1k of visible characters per row). It takes forever to open (1.5 minutes on this fast laptop despite 50G of available RAM) and simple operations (insert a row, fill down a few cells) take 25 to 30 seconds. I decided to chop it in half and process two separate tables. So I deleted half the rows and saved it as part 1. The resultant table was more or less the same size as the full version! Madness. Why?