Default values for variable in a report not possible

Dear Experts,

I have desinged a query which is having a variable for Fiscal Period and that is mandatory.

Again in my key figures i have restriced a key figure with this variable and offseted it for previous year and also few more offsettings have been done to dervive month wise trend.

The problem is that

I want the report to run without the variable being popup so that it will run for current month by default and then after the report is being run, i want to give a dropdown box where user can select the value.

i tried to do it in web template initial report is runing fine but i am unable to change the values after that.

any suggestions.

Regards

Neel