I thought I'd do some googling. Which is easy. But actually coming up with an answer proved anything but. Here's the best I could find:
5. Beat severely; slang.
So, that's what they mean.
What this shows is league ranking - ie if you’re first in the Premiership you get a ranking of 1; if you are first in the Championship you get a ranking of 21 etc - versus the percentage of seats occupied.
The blue line is an Excel-generated trend line. And it would appear to show that the better you are doing the better you fill your ground.
Interesting outliers. The one furthest away from the line right down there at the bottom is Darlington. 25,000 stadium, restricted to 10,000 due to inadequate roads. And they can’t even fill that. The big outlier above the line is Norwich. No idea why. Support for Delia Smith or something.