I think I get it now... maybe...
Are you creating a new database every year? That's kinda what it sounds like... If so, what you wanted to do is create a new database after Year 1, and then open that same database when it was time to import Year 2 and later, so that all the data is in the same file.
Fear not, though... if you have a database for each season, it shouldn't be too difficult to fix, especially if you have each season's data in your "data" folder (next to your "website" folder, usually).
But before I get into the solution, let's make sure we have the right problem first.