We had reported how Tesla will not be ordered to recall its semi-autonomous cars in the US, following a fatal crash in May 2016. The US National Highway Traffic Safety Administration closed its investigation after it found no evidence of a defect in the vehicle.

But buried in its report were some actual statistics which showed that Tesla’s Autopilot had reduced crashes by more than 40 percent. This would be considered a vindication for the safety of any car product since the introduction of seat belts.

Tesla vehicles come with the hardware necessary for Autopilot, but need a software upgrade that costs thousands of dollars to make it work. Since buyers can add Autopilot features after purchase, this provides a perfect before and after comparison.

According to the data Tesla gave investigators, installing Autopilot prevents crashes—by an astonishing 40 percent and the NHTSA issued these details while concluding its investigation.

Approximately one third of the mileage on the cars was logged before the upgrade to Autosteer (the most controversial component of the driving suite), while the remaining miles were accrued after installation.

Tesla rolled out a new version of its software in November, known as Tesla 8.0. The update requires drivers to touch the steering wheel more frequently and increases Autopilot's reliance on radar, in addition to cameras and ultrasonic sensors.Tesla Chief Executive Officer Elon Musk said 8.0 would have been able to detect the truck that was involved in the fatal broadside accident.