Player rating for tournaments across all installments of Heroes.

Let me clarify a small point regarding the aging of ratings. It's the current rating that ages, not the annual one. Is the annual rating simply the sum of current ratings? If so, then the annual rating also ages. Wouldn't it be simpler to do this: the rating doesn't age, but it's reset every year. And the player's profile (or the final table) would display the previous year's result.