Current year /last year in reports

I need to report summarised data for range of periods and I need to compare the current year results with last year.

For example I need to report Jan to June of current year and compare in the same reports the results of last year.

How to select the last year? I tried with offset (year-1) but it does not work.

Since I am giving the range of period( 1 to 6) in selection the period , hence the offset does not populate.

Sure mark for helpful answers.