Between June 2018 and December 2022, Tesla released quarterly safety reports citing average miles between crashes for Tesla vehicles. Prior to March 2021, crash rates were categorized as 1) with their SAE Level 2 automated driving system Autopilot engaged, 2) without Autopilot but with active safety features such as automatic emergency braking, and 3) without Autopilot and without active safety features. In January 2022, Tesla revised past reports to reflect their new categories of with and without Autopilot engaged, in addition to making small adjustments based on recently discovered double counting of reports and excluding previously recorded crashes that did not meet their thresholds of airbag or active safety restraint activation. The revisions are heavily biased towards no-active-safety-features$\unicode{x2014}$a surprising result given prior research showing that drivers predominantly keep most active safety features enabled. As Tesla's safety reports represent the only national source of Level 2 advanced driver assistance system crash rates, clarification of their methods is essential for researchers and regulators. This note describes the changes and considers possible explanations for the discrepancies.

翻译：2018年6月至2022年12月期间，特斯拉发布了季度安全报告，其中引用了特斯拉车辆在碰撞之间的平均行驶里程。在2021年3月之前，碰撞率被分为三类：1）启用SAE L2级自动驾驶系统Autopilot时；2）未启用Autopilot但开启主动安全功能（如自动紧急制动）时；3）既未启用Autopilot也未开启主动安全功能时。2022年1月，特斯拉修订了以往的报告，以反映其新分类（即启用和未启用Autopilot的情况），同时基于近期发现的重复报告问题进行了小幅调整，并排除了此前记录中未达到安全气囊或主动安全约束系统激活阈值的碰撞事件。这些修订明显偏向于无主动安全功能的场景——这一结果令人惊讶，因为此前研究表明驾驶者大多会保持多数主动安全功能处于启用状态。鉴于特斯拉的安全报告是唯一全国性的L2级高级驾驶辅助系统碰撞率数据来源，澄清其方法对研究人员和监管机构至关重要。本文描述了这些变化，并探讨了导致数据差异的可能原因。