In March 2020, Los Angeles’ public-transit agency, Metro, stopped collecting fares on its buses as a COVID-19 safety precaution. For the next 22 months, Metro waived fares for anyone who wanted to keep riding its buses, anywhere they wanted to go (as long as they wore a mask, of course). And people did keep riding. Outside of the initial stay-at-home order in the spring of 2020, Metro’s ridership never dipped below 50 percent of before-times ridership, with buses eventually recovering to within 10 to 15 percent of pre-pandemic numbers.

While the agency doesn’t know exactly how many people were riding fare-free buses during this time — because fare collection is one of the ways to track ridership — a spokesperson says that from April 2020 to December 2021, it’s safe to say Metro’s buses provided about 281 million fare-free boardings. This means the agency has inadvertently been conducting what may be the biggest free-transit experiment in U.S. history.