Pivot calculation problem - Calculation addressed to mounth column which is changing

Hello i need help!

In the pivot table I have calculations that are bound to columns with months (12 months)
offcourse next month I enter new data and the month is shifted or deleted than calculation collapsed. Any idea how i fix that?

tnx for help really!
LP

Hello Zeko, Can you please upload a sample file showing how it looks and how do you want to see it.
Best Regards/VKS