How competitive are USTA League matches? Interesting tennis league stats

USTA League tennis is level based using the NTRP (National Tennis Rating Program) system and is design to promote competitive play for recreational players.  That begs the question, how competitive is the play?

I've looked at the competitiveness of matches before in writing about playing up and its effect on scores, that analysis looking at how close scores are.  That showed that 60-80% of matches were close depending on your definition.

But another measure is a player's individual record and this is a statistic more people are familiar with and tend to track.  In an ideal world, one might expect that every player would have a winning percentage right around 50% since everyone winning and losing half their matches would indicate the matches must have been competitive.  We know in reality that isn't going to happen, and to be honest, being competitive doesn't mean you are winning and losing the same amount, as while it is fairly unlikely this would happen, you could have competitive matches (say 6-4,6-4 scores) and lose every match or win every match.

I couldn't just leave this one alone though, I had to do some analysis.  Below is a chart showing the distribution of winning percentages from 18 & Over and 40 & Over play for 2017 for players that played at least 5 matches.

We see that nearly half of the players do win between 35% and 65% of their matches.  If you extend it out to 25% to 75%, the number jump up to 70% of players.  So if your measure of competitiveness is match winning percentage, 70% of players appear to have a competitive experience.

It is interesting that the number of players in the ~40% and ~60% bands is larger than those in the ~50%.  I'm not sure a good explanation for this other than any player playing 5, 7, or 9 matches in the year cannot fall in the ~50% band, so perhaps that is it.

Note that with a fair number of players playing up, the handful of players with very poor/excellent records is perhaps not surprising.  You would expect some number of uncompetitive matches from these matches.

But even with the range for each NTRP level, when at-level higher rated players play lower rated ones, you will see lopsided results quite often and this is somewhat expected.

It is always interesting to see how the different genders fare with these sort of stats, so here are the women.

And the men.

There are slight variations, but really, no significant differences for men vs women.

What do you think?  Is the distribution of winning percentages what you would expect?  Do you think USTA League matches are generally competitive?  Or are the ranges for the NTRP levels too large?