Actually this isn't the correct way to do this, since it won't work correctly on certain days. The Help section says so change the print date to do this, but you might be able to use the following:
{table.date} in currentdate - dayofweek(currentdate,7) - 6 to currentdate - dayofweek(currentdate,7)
...where the "7" designates the starting day of the week. You should test this to see if works as expected.
-LB