Frustration and boredom are two emotions I often feel when sitting in traffic. But when I see cars whizzing past me on the car-pool lanes, you can throw in envy.

I can’t be alone in this.

But how often are car pools used?

Among the dozens of great responses I received over the week regarding my column, a woman in Salt Lake told me she can’t help but notice "there is almost no one in the (High Occupancy Vehicles) lanes."

A recent New York Times story notes the percentage of workers who carpool has dropped by almost half since 1980.

That made me wonder: Is Hawaii stuck in some kind of car pool tunnel vision when it comes to traffic solutions?

According to the Census Bureau’s American Community Survey, carpooling to work is in decline. In 2000 there were 107,191 carpoolers, about 19 percent of the commuting population. By 2009 there were 98,316 workers who carpooled to work, about 15.6 percent of commuters.

At the same time, people who drive to work have increased to 421,496 in 2009 from 359,916 in 2000.

Carpooling became a policy idea in the U.S. during the 1940s, when oil and rubber shortages limited the use of personal cars, according to the New York Times. In Hawaii the first HOV lanes were placed in 1979, at the H-1 Airport Viaduct, and on Kalanianaole Highway.

HOV lane usage has been pretty consistent over the years, hovering at more than 5,000 drivers, according to the state. Use of the Zipper Lane — introduced to Honolulu in 1997 — has seen larger drops. In 2007 there were an average of 4,610 drivers in the Zipper Lane. In 2008 and beyond, there have been slightly more than 2,500 drivers in the Zipper Lane.

That’s because the state increased the minimum number of vehicle occupants to three from two in 2008. It’s not certain whether the drop is due to more people piling into cars or people just using the Zipper Lane less.

State transportation spokesman Dan Meisenzahl argues the Zipper Lane is necessary. Just look at the traffic jam that piles up when a Zipper Lane is out due to an accident or other reasons, he says.

And the state is working toward establishing an afternoon Zipper Lane. The state awarded the contract to Hawaiian Dredging in December, but the other two bidders have filed protests.

Under the best-case scenario, Meisenzahl says, the situation will be resolved by August, and the afternoon Zipper Lane could zip open by fall 2013, providing an extra westbound lane on the H-1 freeway.

So it looks like encouraging car pools will still happen for some time. Social media and our tight-knit community make it easy to find others to carpool with. But most carpoolers aren’t going through the state.

In 2005 there were about 1,000 people on the state’s rider-share database. Today the list has about 100 names. Only time will tell how long ride-sharing programs will last.

Gene Park can be reached at gpark@staradvertiser.com or on Twitter as @GenePark.