Excel freezing when saving, but not when Calculating

[atmanley]

I have two excel files, one that contains about 200,000 rows of data, and the other for running calculations off of the data file. I have added 5 cells of Sumifs (and/or sumproducts), which takes excel <10 seconds to calculate... but when I hit save file, excel freezes for 20-30 minutes. Why is saving an intensive process compared to the actual calculations?

 

[atmanley]

A little more context: I have an i7 processor with 8 cores and 16 GB of memory. All 8 cores are accessible by Excel. When looking at task manager, excel is using 8 GB of memory while attempting to save.