The stat called differential is the Score + minus the Score -.
It's the difference between the points you make and the points you give away.
If you make a lot of points and give away little, you would have a bigger difference. A higher number.
If you make few and give away a lot, you could be in the minuses.
In the example below:
Player 1 has a lot of points, but opponents got a lot of points against him as well.
Player 2 got a lot of points but gave away fewer. We could assume that he wins with a bigger difference in points. Wins 10-2, 10-3 compared to player 1 who wins 10-6, 10-7 perhaps.
Player 7 gives away more points than he makes points. He is at -12.
