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
New York 0 Dallas 1 +0.1
-0.1
DC United 2 Revolution 2 +0.1
Tampa Bay 1 DC United 2 -0.1
-0.3
Crew 4 Wizards 0 -0.1
Tampa Bay 2 Crew 1 +0.6
Galaxy 2 Dallas 1 +0.1
Dallas 1 Galaxy 3 +0.1
Week of 9/20100.0*Chance in playoffs100.0*Average seed
DC United 1 Tampa Bay 2 +0.3
Tampa Bay 1 DC United 5 -0.1
Earthquakes 2 Galaxy 3 -0.1
Dallas 1 Revolution 2 +0.1
Week of 9/28100.0*Chance in playoffs100.0*Average seed
Galaxy 2 Wizards 0 -0.3
Points
Chance Will Make Playoffs