Damage Scaling in Super Street Fighter 4

There are two types of damage scaling in Super Street Fighter 4, with both having an impact on the damage an attack or combo will deal on an opponent. 

The first is Vitality Scaling

As the name implies, the damage is scaled depending upon how much Vitality Guage (health bar) the opponent has when you do damage to him.  Once the opponent is down to 50% or less on their Vitality Guage, your attacks will do less damage.  See the table below for the points at which damage scaling increases and how much damage is scaled back. 

VITALITY SCALING
Vitality Guage of Opponent	Damage Scaling
51-100%	Your attacks do full damage
16-50%	Your attacks do 90% of their full damage
1-15%	Your attacks do 75% of their full damage

The second type of damage scaling is Combo Scaling 

The more attacks that are part of a single combo, the greater the damage scaling that will occur.  You really need to grasp this concept as a player because there are instances where a combo consisting of just a few attacks can actually do more damage than a combo which has many more attacks. See the table below for the effects of Combo Scaling on damage as the number of hits increase.

NOTE: The number of hits in a combo does not impact Combo Scaling damage. It is the number of actual attacks.  A Super Combo consisting of several hits still counts as only one attack.  The only exceptions to this are Focus Attacks and Ultras, both of which count as two attacks.  For example, if you Focus Attack into Ultra, it is considered to be a four attack combo and the combo will inflict 70% of its full damage.

Resets: Combo Scaling is why resets are so important. Resets are where you intentionally end a combo and use other moves or mix-ups to go into a new combo.  Instead of having one long combo which would have its damage heavily reduced due to Combo Scaling, you instead try land two smaller combos which are not scaled as much, so the overall damage output is greater.

Why is Combo Scaling in the game? To keep things fair. Some characters have rely on simpler combos with less hits and attacks. Some characters, such as Sakura, can string together very long combos consisting of many attacks and hits. If it were not for damage scaling, characters like Sakura could be very overpowered.

COMBO SCALING
Attack	Damage Inflicted
First	Your attack does 100% damage
Second	The combo (or Focus Attack or Ultra: See Above) does 100% damage
Third	The combo does 80% damage
Fourth	The combo does 70% damage
Fifth	The combo does 60% damage
Sixth	The combo does 50% damage
Seventh	The combo does 40% damage
Eighth	The combo does 30% damage
Ninth	The combo does 20% damage
Tenth and Higher	The combo does 10% damage

Putting it together

Let's say you do a five attack combo on an opponent who has 35% of his Vitality Guage remaining.  The five attack combo will be reduced to 60% of its full damage due to Combo Scaling.  That 60% damage will further be reduced by 10% (it inflicts 90% of its damage value) due to Vitality Scaling.