When Does the Garage Feel It?

A fleet turnover simulator built on BTS National Transportation Statistics: how long plug-in and self-driving cars take to show up in a 1,000-space garage.

New-car sales move fast. The cars actually parked in your garage do not. Set a scenario and watch how long the fleet takes to catch up.

Data as of Sales history through 2025 Fleet age as of Jan 1, 2025 Latest BTS release used: Mar 26, 2026 Figures checked Oct 1, 2026
NTS Table 1-17b counts zero Level 4 sales in 2020 and 2021, the latest years it covers.
NTS Table 1-26: 12.8 years as of Jan 1, 2025, a record high. Older fleets turn over more slowly.
Quick scenarios
Fleet hits 10%
of cars on the road
Fleet hits 25%
of cars on the road
Fleet hits 50%
of cars on the road
The lag

Showroom versus street

Share of new sales Share of all cars on the road
1 stall = 10 spaces · 1,000-space garage

How it works. Each model year is a cohort of new cars. Cohorts retire on a survival curve calibrated so the fleet’s average age matches the figure you set. Years through 2025 use actual plug-in sales; later years follow your scenario. The garage assumes its parkers look like the national fleet; a downtown or airport facility will run ahead or behind.

NTS tableWhat it suppliesLatest dataBTS release
1-19Plug-in hybrid and battery-electric sales2025Mar 26, 2026
1-17aTotal new car and light truck sales (share denominator)2024Jun 26, 2025
1-26Average age of light vehicles in operationJan 1, 2025Aug 26, 2025
1-17bSales by level of driving automation2021May 26, 2023
1-11Light-duty vehicles registered: 271 million2024Jul 27, 2026

Notes. Plug-in share is Table 1-19 plug-in hybrid plus battery-electric sales divided by Table 1-17a new vehicle sales and leases. Table 1-17a does not yet report 2025, so the 2025 share (9.2%) uses the 2024 total. BTS discontinued Table 4-58 (vehicles scrapped), so retirements are modeled from average age rather than read. Figures update when BTS revises these tables.