Personalization of analyzed time period

It would be great to allow the user to set personalized time periods. E.g. start analyzing from a date D, and then re-initialize the count every N days.

It would be nice to allow the user to set a name for personalized periods (so e.g. I could name it “From mobile contract payment”, or “Hotel wifi used”, so I open notification bar and see: “From mobile contract payment: 2.5 GB”).