Well, if it was migrated to Subversion from CVS on the day Subversion came out, that gets us back to 2000.

If it was migrated to CVS from RCS on the day CVS was released, that gets us back to 1986.

If it was migrated to RCS from SCCS on the day RCS came out, that gets us back to 1982.

SCCS showed up in 1972, just in time for this commit.