How are these numbers calculated?

Big Games

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

Week of 4/8100.0*Average seed
Swindon 2 Tiverton Town 2 +0.0
Week of 4/15100.0*Average seed
Taunton Town 0 Bideford 0 -0.0
Bridgwater Town 1 Taunton Town 5 +0.0
Week of 4/22100.0*Average seed
North Leigh 1 Taunton Town 0 -0.3
Bideford 0 Salisbury 1 -0.2
Points
Chance Will Win Championship