https://www.cnbc.com/2018/01/31/waymo-gm-lead-in-californias-new-self-driving-report-cards.html

California's Department of Motor Vehicles released its annual autonomous vehicle disengagement report today. In the report, all companies that are actively testing self-driving cars on public roads in the Golden State disclose the number of miles driven and the frequency in which human drivers were forced to take control of their driverless vehicles. The biggest takeaway is that this is still Waymo (née Google) and GM's party, and everyone else is playing catch-up.