How are these numbers calculated?

Big Games

How we did last week and who we should root for this week.   Explain

Week of 4/20100.0*Chance wins title100.0*Promoted100.0*Average seed
Ilkeston FC 0 Hednesford Town 2 +16.5
+12.4
+0.2
Marine 1 North Ferriby 3 -15.6
-11.7
-0.2
Week of 4/27100.0*Chance wins title100.0*Promoted100.0*Average seed
North Ferriby 1 Chorley 0 -18.4
-13.8
-0.2
Hednesford Town 4 Stocksbridge 1 +11.0
+8.2
+0.1
Week of 5/4100.0*Chance wins title100.0*Promoted100.0*Average seed
AFC Fylde 1 Hednesford Town 2 +25.9
+19.5
+0.3
North Ferriby 2 Ashton United 0 -20.0
-15.0
-0.2
Points
Chance Will Win Championship