If you want to convince yourself that choking is a thing, then this is a stat you might look at.

But, this stat is just as likely to be more influenced by how close your opponent's skill was on that day (how often you play opponents at a similar skill level), your and your opponent's relative stamina, whether those match points appeared in a regular service game or a tiebreak (how often your style of play goes to a tiebreak), and perhaps even pure luck - out of thousands of tour players, some are going to have incredible luck.