How could I automate a tracking list of "how many projects users were on at given dates"

OliverScheurich 

Thanks for your reply.
I could use Power Query to automate my actions and repeat them to update.

But we'll have to use it on a few PC from the office and can't install anything on most.
That's why I would like to find a way to create a macro/script for it.

The List I made with a manual output could be use as it is. Maybe a simple macro to add an update button.

But my major issue is that dates are going to move. I'm looking for a way to make that button "grab" every single date, from a range (7 columns and 500 rows), and take those individual dates as colum headers (creating new ones if needed and deleting old ones, or plainly overwriting all the old ones) for the Listing.