How are these numbers calculated?

Big Games

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

Week of 4/14100.0*Chance in playoffs100.0*Average seed
Shortwood United 0 Evesham United 4 +20.0
+0.8
Evesham United 2 Bishop's Cleeve 1 +9.1
+0.5
Larkhall Athletic 2 Bristol Manor F 0 +5.0
+0.2
Kidlington 1 Bideford 2 -3.2
-0.2
Shortwood United 0 Wimborne Town 5 -2.7
-0.1
Bristol Manor F 5 Barnstaple Town 1 -2.4
-0.1
Didcot Town 0 Totton 0 +2.2
+0.1
Swindon Superma 1 Winchester City 1 +2.0
+0.1
Swindon Superma 2 Salisbury 2 +1.1
+0.0
Bideford 2 North Leigh 0 -1.0
-0.1
Bideford 2 Paulton Rovers 1 -0.7
-0.1
North Leigh 1 Cirencester Town 2 -0.4
-0.1
Yate Town 0 Totton 1 -0.2
-0.1
Kidlington 0 Salisbury 1 -0.2
Kidlington 1 Swindon Superma 1 +0.1
Wimborne Town 1 Taunton Town 1 +0.1
Week of 4/21100.0*Chance in playoffs100.0*Average seed
Mangotsfield Un 0 Evesham United 2 +24.7
+0.9
Slimbridge 4 Bideford 3 +6.2
+0.2
Bishop's Cleeve 0 Swindon Superma 5 -6.1
-0.2
Cinderford Town 2 Bristol Manor F 0 +5.5
+0.1
Taunton Town 2 Bristol Manor F 1 +3.5
+0.1
Winchester City 1 Cirencester Town 2 -3.2
-0.1
Cinderford Town 3 Bideford 4 -2.7
-0.1
Salisbury 2 Didcot Town 1 +2.4
+0.1
North Leigh 0 Didcot Town 2 -1.9
Salisbury 1 Bideford 0 +1.5
+0.0
Didcot Town 4 Larkhall Athletic 2 -1.3
Cirencester Town 3 Kidlington 2 -0.7
-0.0
Wimborne Town 4 Paulton Rovers 1 -0.6
-0.2
Totton 1 Wimborne Town 1 +0.1
Week of 4/28100.0*Chance in playoffs100.0*Average seed
Evesham United 1 Totton 0 In
+0.7
Didcot Town 3 Paulton Rovers 0 -5.1
-0.1
Swindon Superma 3 Barnstaple Town 0 -4.4
-0.2
Shortwood United 0 Cirencester Town 3 -4.1
-0.1
Wimborne Town 5 Slimbridge 0 -0.2
Points
Chance Will Make Playoffs