How are these numbers calculated?

Big Games

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

Week of 4/20100.0*Promoted *100.0*Average seed
London Wasps 24 Exeter 37 +38.8
+1.0
Gloucester 28 Saracens 23 -9.0
-0.2
Bath 27 Leicester 26 -2.0
-0.1
Week of 5/4100.0*Promoted *100.0*Average seed
Exeter 40 Gloucester 39 Yes
+0.4
Saracens 23 Bath 14 Yes
+0.0
Games Above .500
Chance Will Make Playoffs