Most dramatically, teachers involved in sports have dived from 46 per cent of all secondary school teachers 20 years ago to an all-time low of 29 per cent. High-school students playing rugby have dropped by a fifth, from 30,621 in the year 2000 to 24,731 last year.
Cricket players have almost halved from 17,794 to 9096.
Still, it's not all bad. Steven Adams' success in US basketball has helped propel basketball numbers up by 53 per cent to 25,072, surpassing rugby as the second-most-popular school sport after netball, which has held steady at 27,000 players.
And other new sports which did not even exist in schools 20 years ago have grown quickly, such as futsal (indoor football), waka ama and Kī o Rahi, a seven-a-side touch game which 3224 high-school students played last year.
Softball, whose numbers have halved nationally from 4141 players in the year 2000 to 2101 last year, has been reinvigorated with a safer version called "slow pitching".
Also interesting are the figures on who is leading the sport sessions. Sixty-eight per cent of sports coordinators are female.
The School Sport data shows that school sports coordinators are most likely to be aged 46 to 55 (31 per cent). Another 22 per cent are aged 36-45, 21 per cent are aged 26-35, 17 per cent are aged 55-plus, and only 10 per cent are aged 25 or under.
Not that young people should be lined up and forced into sports camps, at the expense of all other aspects of building balanced lives.
ACC head of injury prevention Isaac Carlson warned in June last year of a growing concern that too much sport may be as harmful for kids as not getting enough exercise.
The agency urged parents to restrict how much organised sport their children play each week by following a guideline of one hour of sports for every year in age. Under this recommendation a 10-year-old would play no more than 10 hours of sport competition, training and PE a week.
Well aware of the benefits however, more schools are looking to once fringe activities such as surfing and skateboarding to impel our young people into exercise. Whatever keeps us moving is the positive change we need to make.