Filter by date variable

I have a Custom Fiscal Calendar table that contains
following:

                  Date,Fiscal Year, Fiscal, Qtr, Fiscal Period, Fiscal Week,  and Fiscal_Year_Week.

I need to create an analytical/calculation view where data is filtered by current and previous fiscal_year_week when the data is retrieved.

For example, today is 08/28/2013 which is fiscal year week of 201335, so I need to filter my data where Fiscal_Year_Week in(201334 and 201335)

The issue is I don’t have anything that tells me what current fiscal_year_week is other than querying the table with date = today() then get the fiscal week year from the record, then subtract 1 for previous week.

I know I can do this by using sql script, but is there any way I can achieve what I need in graphical view?

Any suggestions would be appreciated.

thanks!

Hyun