Differential Ratio, or diff. ratio, is an indicator of the level of asymmetry of the core. The diff. ratio is usually expressed as the quotient of the Total diff. and the Int. diff. Balls with higher diff ratios have a higher degree of asymmetry.
The Int. diff. also tells us how quickly the ball will respond to friction. The higher the value, the faster the response to friction. This is the reason why Asymmetric cores tend to produce more angular break points than Symmetric cores.