Andrew:
I create a Calculated Column as you suggested, as follows: QUERYDATE("Enter the As-Of Date")

As well, I am using the following Filter: {Trx Date} <= QUERYDATE("Enter the Last Date")

The column appears with my As-Of Date, but when I run my View, GV prompts me twice to select a Date (i.e. "Enter the As-Of Date", and then again "Enter the Last Date").

How can I have GV only prompt once for the run date?