I don't know of a way to do that but you can plug this into your query instead of parameters and it will provide the date range you are looking for...
I'm assuming you want the previous week's data and not the current week information here.
So plug this into the criteria of your query.
Between Format(DateAdd("d", (-Weekday(Now) - 6), Now()), "mm/dd/yy"

and Format(DateAdd("d", (-Weekday(Now)-1), Now()), "mm/dd/yy"
If you ran this this week you would get data
Between 5/20/02 and 5/24/02
Next week you would get data
Between 5/27/02 and 5/31/02
One note of caution here. If your field is formatted for DATES AND TIMES, you must add a day to the END date when using the between function because it assumes that the time would be 00:00 so the function would be ...
Between Format(DateAdd("d", (-Weekday(Now) - 6), Now()), "mm/dd/yy"

and Format(DateAdd("d", (-Weekday(Now)), Now()), "mm/dd/yy"
Trisha
padinka@yahoo.com