I have 28 excell spreadshheets with up to 4000 lines and 82 columns in each. There are a few formulas to apply and each spread sheet will be reduced to 50 - 600 lines and about 10 columns. The resulting 28 smaller spreadsheets are then to be assembled into one large spread sheet with the result being one big Excell spreadsheet with about 10,000 - 15,000 lines and 10 columns. It's possible that I would want to add an additional 15 spreadsheets similar to the first batch to the "master" spreadsheet in July.