A new study suggests driverless cars like Waymo may have a safety edge over people behind the wheel, but what is the data actually showing? Waymos make headlines pretty often these days — usually when they shut down in traffic during storms or power outages. But now, a new study from the Insurance Institute for Highway Safety is drawing attention to something else: Waymo’s driverless vehicles may actually crash far less often than human drivers. Stream NBC 5 for free, 24/7, wherever you are. The study by the independent nonprofit examines crash data for four of the U.S. cities where Waymos have been on the road for several years, including San Francisco, Phoenix, Los Angeles and Austin. Looking only at crashes that would typically be reported to police, researchers analyzed Waymo's first 50 million miles of fully autonomous driving and found its crash rate was 68 percent lower than that of human drivers. For comparison, human drivers logged about 200 billion miles in those same areas during the study period. But researchers admit the data isn’t perfect. Gaps in federal crash-tracking data and different reporting requirements make it difficult to fully measure how self-driving vehicles stack up against human drivers. One key limitation is that the federal crash-reporting system for automated vehicles does not consistently collect data on miles driven, making it harder to compare crash rates across vehicle types. So when can you hail a ride in a Waymo in Chicago? A Waymo spokesperson told NBC 5 Responds the framework for their operations in Illinois is still in the works. A bill that would’ve cleared the way for driverless taxis to operate in Illinois has stalled in the legislature.