That's because you're looking at the all time leagues, so the reputation change is measured from the beginning of the site. This is the same for other numbers (5,000+) except for those below 200, because, as indicated at the bottom of the widget,
users with less than 200 reputation are not tracked in the leagues
Some explanation when something like this happens is given in this post on Mathematics Stack Exchange: Why is my total reputation less than my monthly reputation? (You might be also interested in other posts linked there, for example: What are private reputation events?)
I will quote the answer posted there:
The discrepancy is by design:
Total reputation ...