If those same miles had been driven by typical human drivers in the same cities, we would have expected around 13 injury crashes.
I’m going to set aside my distrust at self reported safety statistics from tech companies for a sec to say two things:
First, I don’t think that’s the right comparison. You need to compare them to taxis.
Second, we need to know how often waymos employees intervene. From the NYT, cruise employed 1.5 staff-members per car, intervening to assist these not-so-self driving vehicles every 2.5 to 5 miles, making them actually less autonomous than regular cars.