MS Excel neglects performance cores

Hi,

I have a Macbook Pro, m2 max, running on macOS Ventura 13,6. While using ms excel, version 16.77.1 for mac, I have to spend quite some time waiting for a file to be calculated. Looking at the activity center, I notice that the efficiency cores are being used, but the performance cores are not.

In the excel settings I have set to use all the processors. What can cause the performance cores to be neglected, and how do I get them involved?

I am fairly new in macOS.

Your help will be greatly appreciated.