California’s Department of Motor Vehicles released its annual autonomous vehicle disengagement report today, in which all the companies that are actively testing self-driving cars on public roads in the Golden State disclose the number of times that human drivers were forced to take control of their driverless vehicles. The biggest news to come out of this report is from Waymo, Google’s new self-driving car company, which reported a huge drop in disengagements in 2016 despite an almost equally huge increase in the number of miles driven.

In other words, Waymo’s self-driving cars are failing at a much lower rate, even as they are driving a whole lot more miles. The company says that since 2015, its rate of safety-related disengages has fallen from 0.8 per thousand miles to 0.2 per thousand miles in 2016. So while Waymo increased its driving by 50 percent in the state — racking up a total of 635,868 miles — the company’s total number of reportable disengages fell from 341 in 2015 to 124.