The rate at which new vehicles replace the existing stock of used vehicles affects the rate at which the benefits of regulations requiring safety technologies, controls on pollutant emissions, and energy efficiency improvements are fully realized. A review of past estimates of the life expectancies of U.S. light-duty vehicles indicates they have been increasing by 0.5 % to 1.5 % per year for the last half a century. We estimate models of scrappage rates and survival probabilities as a function of vehicle age for U.S. passenger cars, SUVs and vans, and pickup trucks, using population counts of vehicles in operation by vehicle type and model year for calendar years 2002–2020. Our results indicate that life expectancies for all three vehicle types continued to increase over this recent time period, by 2–3 years for passenger cars, 3–4 years for SUVs and Vans, and 5–6 years for pickup trucks. By 2020, median expected lifetimes ranged from about 17 years for passenger cars to 20 years for SUVs and vans, and 25 years for pickup trucks. The content and durability of new vehicles is likely to continue to increase as the market transitions to more electrified and automated vehicles, with important implications for policies aimed at reducing emissions, increasing fuel economy and improving safety.

新车取代现有旧车存量的速度影响着安全技术、污染物排放控制和能源效率改进等法规所带来的好处的充分实现的速度。对过去对美国轻型汽车预期寿命估计的回顾表明，在过去的半个世纪中，它们每年以 0.5% 至 1.5% 的速度增长。我们使用 2002-2020 日历年按车辆类型和车型年份划分的运营车辆数量，估算了美国乘用车、SUV、货车和皮卡车的报废率和生存概率随车龄变化的模型。我们的研究结果表明，在最近一段时间里，所有三种车辆类型的预期寿命均持续增长，其中乘用车延长了 2-3 年，SUV 和货车延长了 3-4 年，皮卡车延长了 5-6 年。到 2020 年，乘用车的预期寿命中位数约为 17 年，SUV 和货车为 20 年，皮卡车为 25 年。随着市场转向更加电动化和自动化的车辆，新车的内容和耐用性可能会继续增加，这对旨在减少排放、提高燃油经济性和提高安全性的政策具有重要影响。