Variable offset not working

Hello Experts -

I have a structure and a variable with single-value entry. The variable is on 0CALMONTH.

If user input 06/2007, I wanted to see information for 06/2007, 05/2007, 04/2007. I'm using a variable offset. But my report output is always for 06/2007. I have data for 05/2007 and 04/2007 also.

In the column header, it shows 04/2007, 05/2007 and 06/2007 but there's not data.

Can someone please help me with this? What am I doing wrong?