I'm not ignoring that fact. There are two different proration numbers for each move, however only one applies for each hit. The two different numbers are if a combo starts off with that move, and during the move. For example, if an opponent is at neutral and gets hit with the Dbug, the proration number applied is 102%. If they get hit with it while in hit stun, the proration number applied is 99%.
Then there's that weird thing where each character just does a % damage of their own moves, but that's a discussion for a different time and place.