(Reuters) – U.S. motorists drove 11% fewer miles in July than a year ago as drivers stayed home due to the coronavirus pandemic, the U.S. Department of Transportation (DOT) said Tuesday in a monthly report.

U.S. drivers covered 262.4 billion vehicle miles in July, 33.2 billion vehicle miles fewer than the same month a year earlier. The drop came as government lockdowns to stop the spread of coronavirus kept drivers home.

The biggest declines were seen on the East Coast, where mileage in the North fell 15.4% and in the South by 11.3%. Driving on urban Interstate roads fell by 14.8%, the sharpest decline seen in single road category.

U.S. mileage has been below year-ago levels since March, when American businesses and schools first closed due to the virus. The lowest levels were seen in April, when government restrictions were most widespread.

U.S. driving data is closely watched by oil market participants because gasoline and diesel consumption are key drivers of oil prices.