US roads have become more lethal even though Americans are driving less due to coronavirus quarantine and stay-at-home orders, a new report has found.
Early data indicate a year-on-year 14% jump in fatality rates per distance driven in March, the document by the National Safety Council (NSC) says.
The number of miles driven during the month dropped by more than 18%.
However, the overall number of roadway deaths across the US in March fell by 8% to 2,690.
Deaths for the current year have so far totalled 8,460.
Speeding - key factor
The mileage death rate per 100 million vehicle miles driven was 1.22 in March compared with 1.07 in March 2019, the NSC report said.
"Disturbingly, we have open lanes of traffic and an apparent open season on reckless driving," said NSC President Lorraine M Martin.
"Right now, in the midst of a global pandemic and crisis, we should take it as our civic duty to drive safely.
"If we won't do it for ourselves, we should do it for our first responders, our law enforcement and our healthcare workers, who are rightly focused on coronavirus patients and should not be overwhelmed by preventable car crashes," Ms Martin said.
Data suggested that the increase in speeding was one of the key factors explaining the alarming rise in the death rate, the NSC said.
It also said relaxing driving licence requirements for teenagers in some states might have been a contributing factor.
The NSC - a non-profit organisation chartered by US Congress - counts a fatality as anyone involved in a motor vehicle accident: drivers, passengers, pedestrians and cyclists.
The estimated cost of motor-vehicle deaths, injuries, and property damage through March was $95.4bn (£78bn), the report said.