The Supreme Court said in 1977 that having a car was a “virtual necessity” for anyone living in America. By 1997, 43% of the country’s 16-year-olds had driving licences. But in 2020, the most recent year for which figures are available, the number had fallen to just 25%. Nor is it just teenagers. One in five Americans aged between 20 and 24 does not have a licence, up from just one in 12 in 1983. The proportion of people with licences has fallen for every age group under 40, and on the latest data, is still falling. And even those who do have them are driving less. Between 1990 and 2017 the distance driven by teenage drivers in America declined by 35%, and those aged 20-34 by 18%. It is entirely older drivers who account for still increasing traffic, as baby-boomers who grew up with cars do not give them up in retirement.