Since its beginnings in the 1970s and 1980s, tens of thousands of triathlon competitions with various distances have been held worldwide. The number of participating athletes has grown significantly in recent years. There are different records from the associations regarding competitions, starters, and licensees.
USA:
The 2015 Membership Report from the USA lists 161,298 members. Ten years earlier, there were 68,986 USAT members. The 40-49 age group accounted for the highest proportion (40,935 or 30.28%) in the age group comparison. A survey of American USAT members shows a shift in the largest age group from 35-39-year-olds in 2009 to 45-49-year-olds in 2016. The gender distribution was 65% male athletes and 35% female athletes. Triathlon competitions increased from 1,510 in 2005 to 4,339 in 2015. More than half of all respondents had an annual income of over USD 100,000.
Austria:
In 2018, the Austrian association had 37,344 participants in 104 ÖTRV competitions. Of these, 2,536 were licensees. These were divided into 1,799 male athletes (70.94%) and 737 female athletes (29.06%). In 1987, the year the triathlon association was founded, the number of athletes competing in Austrian triathlons was 3,500. 2014 was the year with the highest number of participants to date, with 39,205 starters.
Switzerland:
The annual report of the Swiss Triathlon Federation (Swiss Triathlon) paints a different picture. It shows that participant numbers have not changed significantly in recent years and have even declined slightly compared to previous years. In 2017, 28,328 athletes competed in competitions. This represents a slight change compared to 2011, when the number of participants was slightly higher at 27,864. The association achieved its highest figure in 2015 with 31,637 starters. The number of triathlon competitions fell from 48 in 2011 to 46 in 2017. Most races, namely 53, were held in 2013.
Germany:
In the German association, the number of club members grew by 113% within ten years, from 27,132 (2007) to 57,926 (2017). The number of participants has also doubled in recent years to over 270,000 (2017).

photo by Jon del Rivero on Unsplash