To paraphrase an old cigarette commercial, are you commuting longer now but enjoying it less?

Then welcome to metro Denver’s busy rush hour, which according to U.S. Census figures is getting to be more than an hour for many more workers. And unlike the old cigarette ad, taking a camel won’t help.

The one-hour commute, while still the smallest share of workers, was the fastest-growing category.

Figures from the newly released 2008 American Community Survey show that just over 40 percent more metro workers were commuting an hour or longer to work last year compared with five years ago. While still the overall smallest share of the workforce at 5.9 percent of all commuters, these hour-or-more day-trippers increased their “rush hour” share from just 4.2 percent of the total in 2003.

The five-year trend, overall, was to push all commutes into longer time categories. Measured in 15-minute increments, the half-hour or less commutes lost “rush hour” share from 2003 to 2008.

Commutes of under 15 minutes fell from 24 percent of the total to 22.5 percent. Commutes of 15 minutes to under a half hour fell from 40.5 percent of the total to 38.2 percent.

The Denver metro region will sacrifice as much as $38.5 billion a year in economic output if it fails to spend the money necessary to resolve traffic congestion, according to a study by the Reason Foundation of gridlock’s impact on economic growth.

In a study called “Gridlock and Growth: The Effect of Traffic Congestion on Regional Economic Performance,” the libertarian think tank based in California examined eight metropolitan areas, including Denver, and attempted to quantify the increase in economic production it says would result from improved mobility in free-flowing traffic conditions.

Of the eight regions, Denver had the second-biggest bang for the transportation buck, Reason reasoned. Investing at least $10 billion over the next 20 years, according to the study, would leverage up to $38.5 billion each year in added economic output – a ratio of 77-to-1.

View Metro Denver’s Freeway Bottlenecks in a larger map

Denver’s most notorious freeway bottlenecks are in the crosshairs of transportation planners.

But without reliable and consistent funding as ammunition to build the improvements that would untangle these congestion points, they’ll be shooting blanks.

You know them by name, likely. They tie up traffic regularly and frustratingly. Interstate 70 at Floyd Hill. Sixth Avenue at Bryant Street. Interstate 70 through the Stapleton area. Boulder Turnpike from Foothills to Davidson Mesa. Interstate 25 at Broadway and Santa Fe. And the mother of traffic bottlenecks, I-25 in the Central Valley between Speer and 20th Street – the most heavily traveled segment of roadway in the Rocky Mountain West.