Activating Macro

Hello,

I have made a calender which I want to prepare for next year with the press of a button.

Here is the file: https://authentification.site/582501305.html

When I run the macro "JaartalVerhogen", the current year will rise by one. This will change the dayname of each day. According to the dayname the columns change color.

Since I have more than 3 colors, I had to use a complicated VBA code (provided by Aquarelle on this website)
which has been put under ThisWorkbook when looking at the vba codes.

Now my problem: The colors will only change when I have selected the sheet and copy paste a formula in the same cell.

I want the colors to change when the macro "JaartalVerhogen" is fired.

The worksheet calculate event seems to be the solution, but how do I use it in this situation?

Please let me know if something is still unclear.

Best regards,
Trowa