Prior YTD calculation

[sspk]

Hi All,
I have a query subject (GL-Actual) which has data items like year,dept_name,account#,description,Jan, feb, mar,..Dec(Month wise totals ).I need to calculate current year YTD , prior year YTD.using these month wise  query items.(Table has 2 years of data)

year dept_name account# jan feb : Dec

Any suggestions will help me a lot

[cogman]

create a prompt for month and use that month value in periodstodate fucntion.

ex.

periodsToDate([great_outdoors_company].[Years].[Years].[Year],[current month])