How are these numbers calculated?

Big Games

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

Week of 1/4100.0*Chance in playoffs100.0*Average seed
Newcastle 2 Adelaide 1 In
-0.1
Wellington 0 Sydney 2 -0.1
Brisbane 1 Melbourne 2 +0.2
Perth 1 Central Coast 1 -0.2
Week of 1/11100.0*Chance in playoffs100.0*Average seed
Central Coast 1 Newcastle 2 -0.9
Brisbane 0 Sydney 0 -0.1
Week of 1/18100.0*Chance in playoffs100.0*Average seed
Adelaide 2 Brisbane 0 +0.7
Central Coast 2 Wellington 0 +0.5
Newcastle 2 Perth 1 -0.3
Sydney 2 Melbourne 2 +0.2
Points
Chance Will Make Playoffs