Washington, D.C. — New data released by the U.S. Department of Transportation’s (USDOT) Federal Highway Administration (FHWA) show that U.S. driving topped 1.58 trillion miles in the first six months of 2017 – or more than 8,500 roundtrips from Earth to the Sun – continuing a streak of steadily increasing vehicle miles traveled (VMT) that began in 2011.

The new data, published in FHWA’s latest “Traffic Volume Trends” report – a monthly estimate of U.S. road travel – show that more than 280.9 billion miles were driven in June 2017 alone, which is 3.4 billion miles more than the previous June. The increase in driving over the first half of the year highlights the growing demands challenging the nation’s roads, and reaffirms the importance of improving the nation’s infrastructure investments and streamlining the environmental and permitting processes.

The June 2017 report also includes seasonally adjusted data, which is conducted by USDOT’s Bureau of Transportation Statistics as a way to even out seasonal variation in travel and enable vehicle miles traveled (VMT) comparisons with any other month in any year. The seasonally adjusted vehicle miles traveled for June 2017 were 266.6 billion miles. Seasonally adjusted June VMT increased by 1.0 percent compared to the previous June. The estimates include passenger vehicle, bus and truck travel.

In June, U.S. drivers increased total mileage among all five regions of the United States. At 2.2 percent, traffic in the West – a 13-state region stretching from California to Montana, and including Hawaii and Alaska – led the nation with largest percentage increase in unadjusted VMT.

At .5 percent, the North Central region – a 12-state area stretching from North Dakota to Ohio – had the smallest percentage increase in unadjusted VMT for the month.

At 3.5 percent, Oklahoma led the nation with the largest unadjusted single-state traffic percent increase compared to the same month a year earlier, followed by Nevada and Kansas at 3.4 percent and 3.3 percent respectively. At 2.3 percent, Michigan had the nation’s largest unadjusted traffic decrease for the month.

To review the VMT data in FHWA’s “Traffic Volume Trends” reports, which are based on information collected from more than 5,000 continuous count stations nationwide, visit https://www.fhwa.dot.gov/policyinformation/travel_monitoring/tvt.cfm.