How are these numbers calculated?

Big Games

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

Week of 4/5None
Week of 4/12100.0*Chance in playoffs100.0*Average seed
Cobresal 2 Cerro Porteno 0 -18.4
Santa Fe 1 Corinthians 1 -3.7
Week of 4/19100.0*Chance in playoffs100.0*Average seed
Cerro Porteno 1 Santa Fe 0 In
Corinthians 6 Cobresal 0 -0.1
Chance Will Make Playoffs