How Rare Is It To See A World Record Broken In September?

Last Thursday, Australian Kaylee McKeown set a new world record in the women’s 100 backstroke (SCM) with a clocking of 54.56 during the 2024 Australian Short Course Championships.

Any world record is an incredible feat on its own, but this one is particularly notable because it was set in September. In general, the month tends to lack major meets (though not always the case).

How rare is it to set a world record in September? And what is the frequency we see records broken in the other months?

It’s true that world records in September have not been frequent in recent years. In the last decade, none have been set in long course meters, and only two in short course meters.

 

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But historically, it’s different. In long course meters, no fewer than 134 world records have been set in September since 1957, when World Aquatics started recognizing world records only in metric measurements. This is third only to August (492) and July (362), the months that usually host the primary championships of the year. Some of these competitions have also taken place in September, such as the 1972, 1988, and 2000 Olympic Games and the 1973 and 1994 World Championships, hence the high number of records in this month.

But in this century, major meets in long course meters have not been held in September. That’s why, since 2001, only three world records have been set in September in 50-meter pools, one of which was in an individual event (Japan’s Akihiro Yamaguchi in the 200 breaststroke in 2012) and two in relays, in the 4×100 freestyle and 4×100 mixed medley, in 2013, by the Indiana University team, shortly after World Aquatics began recognizing world records in mixed relays.

As for short course meters, we’ve seen records come more frequently in September. Since 1991, when World Aquatics began recognizing world records in 25-meter pools, there have been 27 global standards, 16 of them in this century. This doesn’t come close to the most prolific months, November (98) and December (187), months that have hosted several stops of the World Cup, the International Swimming League and the World Short Course Championships. But there have been World Cup legs held in September, as well as some relevant national championships, such as the Australian Nationals, so world records in September have not been so rare, at least in short course meters.

Trivia: In short course meters, there has never been a world record in May. And there’s only ever been one in June: Australia’s Michael Klim, in the men’s 50 butterfly in 2000, in a solo time trial at the Australian Institute of Sports in Canberra.

Since the start of the 21st century in long course meters, there have been no world records in November, and only two in December. They records broken came from American Randall Bal in the men’s 50 backstroke in 2008 at the Dutch Swimming Cup in Eindhoven, and Brazil’s Cesar Cielo in the men’s 50 freestyle in 2009 at the Brazilian Nationals. The latter still stands today.