Ok I have an exanple workbook attached.
The situation:
I have date waith ID numbers and amounts for months in the columns.
Then I have an overview sheet in which it should show a summarized view.
Now the formula has to sum for each ID the amount in the respective month.
However I need YTD amounts.
So in the JAN column it should sum form the data BB (beginning balance) and FEB column for that ID.
For FEB it should sum in the columns BB/JAN and FEB and so on.
Hope it makes sense.
Example attached.
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