A coworker of mine was complaining that her shared excel spreadsheet was slow, I checked the file size and its 80 megs! I tried reducing the size by removing formatting from all the empty cells but when I saved it and checked the size it actually got bigger. Any suggestions??

Howdy. A few suggestions:

1. Be sure that all your data sheets are listed alphabetically first. I usually have A0_Data0, A1_Data1, A2_Data2, etc. Then have all your other worksheets base on this data and if others use some of the secondary formula sheets, make sure they always look back, never ahead, i.e. B3_Formulas can look back to any data sheet (A's), as well as B0_Formulas, B1_Formulas, and B2_Formulas. But B3_Formulas should never point to D4_Secondary Formulas. The calculation sequence is critical, especially with larger workbooks.

2. Make sure the formulas point the right way (Top-down, left-right) is the best sequence.

3. Don't leave gaps in the worksheet; it is better to have two tables on different worksheets than to have two tables with excess empty cells between them. You might be surprised at how much is in the worksheets that cannot be seen. One way to do that is go to the edge of your data, then one column over and press ALT + SHIFT + RIGHT arrow, then CTRL + SHIFT + DOWN arrow. Then delete. Go to row below bottom of data and press CTRL + SHIFT + DOWN arrow, then ALT + SHIFT + RIGHT arrow. Then delete. Then save.

4. Certain formulas can be hogs: arrays, UDFs

5. Formatting can add considerable bulk, even simple formatting. So also Conditional Formatting.

6. Check named ranges. If any data is imported from databases, it will have named ranges. Delete any that you don't need (i.e. if you are not going to update - but if you will update, then don't delete the names).

7. If VBA is included, there are ways to reduce that file, but generally not critical.