I have a spreadsheet with a few macros that I open and execute about several
times a day for the past year. I noticed that the file size increased from
less than 100 bytes to 5 MB. There has been no increase in the cells and/or
macros.
The macros include moving/deleting cells. These are repetitive macros that
has to be executed hourly.

Is there any explanation for this? Is there a way to "optimize" (defrag?)
this file?