This point is very important. Given that salary is not distributed evenly saying a top 3, top 5, top 10 payroll is fine for quick & dirty purposes but doesn't really tell you much outside of a general range within league context. Looking at the 2015 opening day payrolls the mean payroll was approximately 125 million with a standard deviation of about 45 million. With that in mind the best way to group teams based on opening day payroll for 2015 would be as such... 3+ Standard Deviations above mean (Super Duper Mega Rich) (LAD $273) 2+ Standard Deviations above mean (Super Mega Rich) (NYY $219) 1+ Standard Deviations above mean (Mega Rich) (BOS $187, DET $174, SFG $173) 0-1 Standard Deviations above mean (Rich) (WAS $165, LAA $151, TEX $142, PHI $136) 0-1 Standard Deviations below mean (Status Quo) (TOR $122, STL $121, SEA $120, CHN $119, CIN $117, CHA $115, KCR $114, BAL $110, MIN $109, MIL $105, COL $102, NYM $101, SDP $101, ATL $98, ARI $92, PIT $88, CLE $86, OAK $86) 1+ Standard Deviations below mean (Poor) (TBR $76, HOU $71, MIA $68) With those groupings established, 3 of the 9 teams in the rich & above brackets (33%) qualified for postseason play, 6 of the 18 teams in the status quo (33%) qualified for postseason play and 1 of the 3 poor teams (33%) qualified for postseason play. You've done all of this nice analysis and then you took it and based your conclusion on a 1 season sample. Sorry, I'm at work right now and wasn't able to do the math for all 17 years that data is available on steve the ump's website. If you'd like to go through and do all the compuatations for me it will save me quite a bit of time when I get home.