How are these numbers calculated?

Big Games

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

Week of 4/13100.0*Average seed
Stotfold 2 St.Margaretsbry 3 -0.1
Biggleswade Utd 1 Hanwell Town 2 +0.1
St.Margaretsbry 1 Ampthill Town 4 +0.0
Week of 4/20100.0*Average seed
Hanwell Town 0 Harefield Utd 1 -0.3
Oxhey Jets 3 Hanwell Town 1 -0.2
Ampthill Town 3 Hertford Town 1 -0.1
Ampthill Town 3 Oxhey Jets 2 -0.1
Berkhamsted 2 St.Margaretsbry 4 -0.1
Week of 4/27100.0*Average seed
Stotfold 5 Hanwell Town 1 -0.3
Tring Athletic 0 Ampthill Town 2 -0.3
Points
Chance Will Make Playoffs