I started in 2011!

Can confirm that everyone who started with me at our gym have since quit. (They were wimps.)

The double guard pull became popular :)

It doesn't look that drastic. What happened in 2001/2002 that caused a small drop before it started to pick back up in 2003? My best guess is there's just probably some variation among the population on here. If you don't look at 2009/2010 then it looks pretty flat between 2008 and 2011 (similar to 2012/2013) so we could also try to ask "What happened in 2009/2010 that so many extra people started BJJ those years?"

I suspect this is more of an effect of the training time...

People who show up as started before 2010 are the black belts here. You don't quit at black (or even brown) that often.

People started in 2010-2013, where there is the flat curve and the drop in 2011 have mostly dropped out (and are not registering to Beltchecker)... They are the ones who should have 7-10 years of training time by this point. From personal experience I know a ton of people who started around my time and have since quit.

When things start to pick up again at 2015 those are people registering who have less than 5 years of training time. Thoise blues & purples who have not quit... yet! :D

I opened my own gym in 2011...sorry everyone....sorry. My bad.

So bad you had a negative amount of people start Jiu Jitsu?? :D

I'm guessing the difference between 2010-2011-2012 is not statistically significant.

Didn't you go on your worldwide BJJ trip in 2011? Maybe it wasn't as inspiring as you had hoped.

Or maybe the sport picked up after I had published that book in 2012?? :D

Wish I started in 2011

You guys do remember that there was a massive financial recession in the USA in 2008-2009 right? So a bunch of people entering the work force and stuff from 08-11 likely didn't have the spare cash to spend on what is a relatively expensive hobby.

Dot com bubble burst in 2000. The economic downturn peaked in 2002. 2008 world wide recession peaked in 2011. That is my guess.

That's when I started. I remember that Summer 2011 was a tough time. It was hard to find a job. Lived that summer with a 50 euro budget, dumpster diving a little bit for food. Maybe it was the same for many others.