Of crashes this year across all classes in MotoGP ! https://motomatters.com/blog_entry/2017/11/23/guest_blog_mat_oxley_motogp_2017_1126.html
Thought that was the number of crashes and red flags at No Limits trackdays this year. Then realised that’s way too low
"During the 1949 season the average winning margin was 46 seconds; in 2017 the average gap was 2.11 seconds, with more than half the races won by less than 1.5 seconds."
the interesting point about the margin is that you get more "racing" injuries - people don't fall off and die of stonewall, but because the bikes are so close, the difference is the risk the rider is willing/able to take. Moto2 is the ultimate for that, and it is a bit crazy at times. The big risk crash now is crashing in a pack and being hit by another bike. How moto3 has avoided more serious injuries in that way is presumably down to all riders being super-young and so super-bouncy, and the bikes not being too heavy or too fast, so inflict less injury when they hit.