You'll all be hearing a lot about the trains I commute to and from work on, and as time goes on you'll realise why, but I was just checking the operating company's online timetables to see if my train's on time tonight and I noticed that the company has an online newsletter. So I had a look, as you do, and I found their description of Public Performance Measure, which basically works out how well a company is doing by comparing train arrivals with published timetables.
Apparently, and I'm not kidding here, for short-distance journeys such as the ones my operating company runs, trains that arrive less than five minutes later than scheduled are deemed to be on time.
Now, maybe it's just because I'm getting old, but I used to think that if something wasn't on time, it was late. It never occurred to me that there might be a sort of fuzzy five-minute window where everything was still fine and dandy.
The possibilities for this admirably laid-back philosophy seem endless. I could tell my editor that my copy isn't late so long as I get it filed less than five days after the deadline. The BBC Ten O'Clock News could tell viewers that so long as the programme doesn't start after 10.05 it's still starting on time.
Mostly, though, I think it's just a cute way of massaging the figures. And why stop at a five-minute limit? Why not ten? Fifteen? Everything would, after all still be on time.