Perhaps a data model something along these lines. A bit simplistic, as I'm guessing you want QTD and YTD when your selected month isn't the end of a quarter or year, but the same idea could be extended. Given a selected period and month, the first table gives you a list of text values that stand for date ranges, which the second table maps to the dates themselves. You would use the Date Key here as one of your dimensions in the chart.
Select Period, Select Month, Date Key
...
Prior Periods, Aug 2016, Jan 2016
Prior Periods, Aug 2016, Feb 2016
Prior Periods, Aug 2016, Mar 2016
Prior Periods, Aug 2016, 2016 Q1
Prior Periods, Aug 2016, Apr 2016
...
Prior Periods, Aug 2016, Jul 2016
Prior Periods, Aug 2016, Aug 2016
Current Period, Aug 2016, 2016 W31
Current Period, Aug 2016, 2016 W32
Current Period, Aug 2016, 2016 W33
Current Period, Aug 2016, 2016 W34
Date Key, Date
2016,2016-01-01
2016,2016-01-02
...
2016,2016-12-31
2016 Q1,2016-01-01
2016 Q1,2016-01-02
...
2016 Q1,2016-03-31
...
2016 Q4,2016-12-31
Jan 2016,2016-01-01
Jan 2016,2016-01-02
...
Jan 2016,2016-01-31
...
Dec 2016,2016-12-31
2016 W1,2016-01-04
2016 W1,2016-01-05
...
2016 W1,2016-01-10
...
2016 W52,2016-12-26
...
2016 W52,2017-01-01
