I don't know MSSQL specifically, but 36 million rows is not large to an enterprise database - working with mainframe databases, 100,000 rows sounds like a configuration table to me :-).
While I'm not a big fan of some of Microsoft's software, this isn't Access we're talking about here: I assume they can handle pretty substantial database sizes with their enterprise DBMS.
I suspect days may have been too fine a resolution to divide it up, if indeed it needs dividing at all.