Thread:Project:Current issues/Diff size in user contributions

Looking at my contributions, I notice that the diff size (the plus or minus number after the timestamp, diff, and hist links) is way too high in all cases. E.g. for this negative diff I get "(+34,826)‎".

The problem isn't restricted to my contribution history, e.g. has the same problem. My contribution history at en-wiki doesn't have this problem. Do other editors have the problem here?