Copy data from one sheet to another at the end of every month

I have a Google Sheet where I track the performance of multiple campaigns.

I want to copy the completion value to another sheet at the end of every month. Each month should have it's own column. This is how it should look:

Right now, I manually copy paste the completion values into the empty columns adjacent to the relevant month and subtract the previous month's values to get the increase in campaign completion. Then that % is multiplied with the total value to get the amount I accrued for that month.

How can I automate the process so that the data gets added from the Campaign sheet to a new sheet at the end of every month?

Is there a script for this?