Referencing Todays Date for Dynamic Date Calculations (Example SDLY)

I know Metabase has the now() function but it only provides current time - i cannot seem to find anywhere how to get current date. Either I am missing something or metabase is severely lacking in this - any advice would be much appreciate!

As an example, trying to simply take a existing date field in my database, and do something like [DATE] - 365 and then sum totals based on that. I don't want to specify a date since it should be a moving report (EG: Today vs. SDLY)