Hello @Alicia779,
I am not quite sure what your inquiry is, are you having issues with copy-pasting in Excel and the program going to "not responding" and crashing, or is Excel just slow and still performing the work?
If you are working within a big file with many formulas, there is a number of things that you can do to increase the file performance and stability. The most harsh form of solution usually is to copy everything over into a new file, as sometimes the files themselves break when they crash too often. Generally, best practice includes removing the number of formulas, or reducing the amount of data in the file.
So as a possible solution for you: if you work with financial data, split off historic data belonging to closed periods. For instance, if you have a file with all the data of the past ten years, you will probably not need the data that is 2+ years old. Retire your current file and start a new one, copy over all the data of the past two years and start a new with the file. You can do that once every year if you want and thus keep all data archived safely and still keep the files working well.
Typically, Excel files lose performance through both the amount of data and formulas, and the issues increase exponentially, since with every extra line of data, one line's worth of formulas get added.
If that solves your issues please let us know. Otherwise perhaps try to give us a better explanation of your issue.
