Have a look at the stats from the link I posted, a lot of GKs have conceded more goals than they should have. There’s a glossary of what each field means.
I’ll use Cov as an example:
As a team, our xG ‘post-shot’ for goals conceded is 52.1 goals, and the goals we’ve conceded (non-FK and penalties) is 55. Therefore, on this metric, we’ve conceded 2.9 goals than we should have.
We’ve had two GKs this term, let’s see how they’ve faired based on all the shots each GK has faced:
1) Wilson - PSxG is 21.3, he conceded 25 goals (excluding FK & PK) so he conceded 3.7 more goals than he should have.
2) Collins - PSxG is 30.9, he conceded 30 goals (excluding FK and PK) so he conceded 0.9 goal less than he should have.
I hope this is helpful and might be an interesting visual for anyone interested.