NEW YORK (CNN/Money) - Sport/utility vehicle registrations in the United States increased 56 percent in just five years, according to a report released Thursday by the U.S. Census Bureau.

SUV registrations went from 15.5 million in 1997 to 24.2 million in 2002, the most recent year for which data is available, according to the Census Bureau's 2002 Vehicle Inventory and Use Survey.

"Altogether, SUVs traveled nearly 315 billion miles on the nation's highways in 2002, up 100 billion miles from 1997," said Census Bureau Director Louis Kincanno. "Collectively, SUVs made the equivalent of more than 650,000 round-trips to the moon in 2002."

In 2002 there was approximately one registered SUV for every eight licensed drivers. Colorado and Wyoming had the highest concentrations with one SUV for every five licensed drivers. (That means that the SUVs in those states could, theoretically, hold all the licensed drivers in the state in reasonable comfort.)

The District of Columbia had the lowest concentration of SUVs, with just one for every 14 licensed drivers.

California had the most SUVs in 2002 -- 2.8 million -- with Texas a distant second with 1.8 million.

Other types of truck-based personal transportation also continued to increase in popularity.

Minivan registrations increased 17 percent between 1997 and 2002. Pick-up truck registrations increased by only 5 percent, but the 38 million registered were still the majority of light trucks.

Across the nation, there was one registered pick-up in 2002 for every five licensed drivers.

West Virginia had the largest increase in pick-up truck registrations, with registrations increasing by 38 percent. New Jersey, with a 25 percent increase in pick-up registrations, was also among the states with the largest increases.

About 77 percent of all trucks were used for personal transportation in 2002, while only 19 percent were used for business purposes.