How many total cave dives per year on Earth?

[rjack321]

I tried to piece together some numbers from GUE's annual reports. If you connect all the dots in the given data, you'd come to about 100 newly certified Cave 1 divers per year in recent years, earlier years maybe half that. If the numbers in the report are correct and the charts are to scale, then I'm pretty confident in this number. They also state that on average 39% of Cave 1 divers go on to complete Cave 2.

I'll let you make your own guesstimates on how active those divers then are. Some will dive a lot, some a bit, some will probably quit at some point. Key will be the turnover, ie how many quit vs how many new ones start. I will also let you make your own estimate about the market share that GUE has on cave training. Based on these two assumptions you should be able to come up with a decent number for total number of active divers per year.

Why start with C-cards at all? They dont mean much beyond the first couple years due to high rates of attrition.

Instead you could look at the number of divers signing into Ginnie Springs (pretty much THE busiest single cave anywhere although for years Dos Ojos was close). Ginnie alone probably accounts for 20-25% of the cave dives in FL on an average day (roughly 200ish dives would be a reasonable weekend day guess).

You could also look at how many divers are active in the NSS and sister nonprofits - many of whom consider themselves cavers who dive vs cave divers.

 

[1atm]

Why start with C-cards at all? They dont mean much beyond the first couple years due to high rates of attrition.

I agree with you. Unfortunately, sitting where I am sitting right now, is very far away from any of the big and busy caves, so that's the only hard data that I could dig up on the interwebz ;-)