How are these numbers calculated?

Big Games

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

Week of 9/13100.0*Chance in playoffs100.0*Average seed
DC United 1 Miami Fusion 3 +31.7
+1.3
Miami Fusion 4 DC United 3 +21.1
+1.0
Tampa Bay Mutin 2 Red Bulls 1 -8.4
-0.2
Revolution 3 Tampa Bay Mutin 0 +6.9
+0.0
FC Dallas 1 Earthquakes 3 -0.2
Earthquakes 0 Galaxy 0 -0.0
Week of 9/20100.0*Chance in playoffs100.0*Average seed
Crew 3 Tampa Bay Mutin 4 -29.8
-0.8
Fire 3 Revolution 2 +1.7
+0.1
Galaxy 0 Earthquakes 1 -0.2
Week of 9/27100.0*Chance in playoffs100.0*Average seed
Miami Fusion 1 Tampa Bay Mutin 3 Out
-1.4
Earthquakes 2 Wizards 0 -0.1
Points
Chance Will Make Playoffs