YTD value minus prev mth value = curent month - Rolling Report
 

Rolling report means the values are updated each month
and i want an easy "automated" way to "update" the amounts each month end.
It is a report of all expenses for the month

First report Jan will start with a 3 column spreadsheet.
1st column Previous month amount (which in Jan will be "0")
2nd column current month (formula will be YTD minus Prev mth)
3rd column year-to-date amounts ( this will be linked to the current trial
balance report

So, next month Feb report, I want to only do "minimal" "moving of columns"

The Jan report "ytd" will now have to be "prev mth amounts" on the Feb report
and "current column will be YTD minus prev
and ytd column will come from the "link" to trial balance that i import in.

an anyone help?