85th Percentile

Outdoor parking lot full of cars

Cars Are Outgrowing Their Parking Spaces

As American vehicles grow taller, wider, and longer, more of them are having a hard time fitting in traditional parking spaces.

February 10, 2023 - Vice

Highway Speed

The 85th Percentile Rule, Explained

A video explainer of the notorious traffic law that explains why some cities have to raise speed limits to enforce traffic safety.

October 8, 2020 - Grist


It's Time To Reconsider How Speed Limits Are Set

Speed limits are currently determined by a calculation that considers only the status quo of vehicular velocity. Standard practices for speed limit setting and legislators should prioritize the safety of community members, according to this article.

August 9, 2020 - Forbes

Parking and Driving

NACTO Recommends Default Safety Setting for Speed Limits

A step toward an overhaul of the way speed is managed on city streets around the country.

August 2, 2020 - Smart Cities Dive

Cars and Herbie

How the Law Enshrines Car Dependence

Land use regulations provide exhibit A in this indictment of the American legal system's support for a murderous and destructive dependence on automobiles for transportation.

July 10, 2019 - The Atlantic

Highway Speed

California Bill Sets Its Sights on Lower Speed Limits

A proposed bill in the California State Assembly would make it easier for local jurisdictions to set lower speed limits, sidestepping the controversial 85th percentile rule.

March 6, 2018 - Streetsblog California

Speed Limit

Raising Speed Limits in the Name of Traffic Safety

Business Insider offers a platform for an argument favored by the National Motorists Association and a particularly vocal Michigan state police officer: that speed limits are too slow to be safe.

November 8, 2017 - Business Insider

Speed Limit

The Origins of Speed Limits

Motor vehicle crashes claim over 30,000 lives per year, with related costs in the hundreds of billions. While we sometimes view that frightening statistic as inevitable, there are reasons to reexamine speed limits and how we set them.

August 2, 2015 - Five Thirty Eight

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