The nation's capital doesn't have the worst traffic in the U.S., but it does fall in the 10 most congested cities in the country, according to a new study. Globally, D.C. traffic is worse than Istanbul, Turkey, according to the global scorecard produced by data firm, Inrix.

WASHINGTON — The nation’s capital doesn’t have the worst traffic in the U.S., but it does fall in the 10 most congested cities in the country, according to a new study.

D.C. is the 6th most car-clogged city in the U.S. — and No. 15 in the world, according to a global traffic scorecard compiled by data firm Inrix.

Globally, traffic congestion around D.C. is slightly better than in Mexico City and slightly worse than in Istanbul, Turkey, according to the scorecard.

D.C.-area commuters spend 61 hours caught in traffic congestion each year, according to the analysis. During peak commuting periods, about 20 percent of motorists’ time is spent idling in traffic.

The congestion costs each D.C.-area driver nearly $1,700 per year — or more than $2.9 billion to the region’s economy as a whole, according to the study.

Report authors said the costs come from wasted time and fuel and from indirect costs, such as increases in household prices when freight trucks get stuck in traffic.

The worst traffic in the U.S. was Los Angeles, where drivers spent 104 hours each year stuck in traffic. That was followed by New York, San Francisco, Atlanta and Miami.

Overall, the U.S. is the fourth most traffic-congested country in the world— after Thailand, Colombia, Indonesia and Russia — with an average 42 hours annually spent stuck in traffic.

The analysis is based on anonymous, real-time GPS traffic data. The analysis considers several factors, including travel time during peak periods on highways in and of the area and within the city itself.

Last week, the District Department of Transportation released its own study of traffic congestion based, in part, on Inrix data, which found the worst traffic congestion in D.C. during the evening commute. The percentage of D.C. roadways where congestion significantly slows traffic is five times higher during the evening commute than during the morning commute, the report found.

The D.C. roadways with the highest levels of congestion are the Key Bridge heading into D.C. and the Southeast Freeway, according to the District’s study.

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