For my planning tool I have two cubes for counting the value of the fixed assets: one with yearly figures and one with monthly figures.
the monthly figures cube is filled with investment data per month and depreciation per month.

I use a nexel writeback to calculate a closing balance per month. and the opening balance of the month is the closing balance of previous month. The starting balance of January however has already been calculated in the yearly figures and I want to push this amount tot he monthly figures as adjustment opening (opening is a formula and cannot get data through a data flow).
Now I use an interactive selection to select the month January when the data comes from the yearly cube. But this is not a final solution.
Is there a way that I can tell the data flow that I only want data pushed to the first month of the year (I already have a selection on entity year and selected only 2019 through a settings cube )?
I tried it with the entity month in the data flow and then an if-statement: if(right(b,2)="01",a,0)

However that did not work