It's probably of little comfort to anyone stuck in gridlock, but the preeminent North American traffic authority says Dallas road congestion went down 18 percent in 2012. INRIX has been creating worldwide traffic scorecards since 2007, and the most recent edition has good news for DFW commuters.

Although our area has previously been ranked as high as No. 5 for overall congestion, Dallas slipped to No. 21 nationally in 2012. The only Texas city that cracks the top 10 is Austin, which ranks No. 4. Houston ranks No. 14 nationally, with drivers wasting an average of 25 hours in traffic each year.

The most congested city in America is — no surprise — Los Angeles, where drivers can expect to annually waste 59 hours in traffic. By contrast, Dallas drivers spend only about 20 idle hours a year in traffic. Austin drivers reportedly spend 38 hours a year in gridlock.

And just what is driving all this congestion? It's the economy, stupid. Traffic across the country dropped 22 percent in 2012 but already is up 4 percent in 2013.

"What we’re finding is as employment rebounds in earnest in the first few months of 2013, so is traffic," says Jim Bak, author of the INRIX Traffic Scorecard.

INRIX calls this correlation "Trafficonomy," and even identified the ebbs and flows of road congestion as related to major economic events such as fiscal cliff negotiations and sequestration, which both triggered a dip in nationwide traffic.

"Every time last year when it looked like we had officially turned the corner in the economy, another looming deadline would approach and traffic — along with hiring and spending — would stall out," Bak says.

The Traffic Scorecard also identified the country's most congested roads, and Dallas had a handful in the top 100. Two portions of Interstate 35 West, Loop 820 West, Interstate 635 East and Stemmons Freeway all made the cut.