Sales of new vehicles continued to dip in the second quarter in another sign that Hawai'i's hot economy is cooling off.

Through June, new-vehicle registrations fell 11.8 percent from last year to 30,461, according to the Hawaii Automobile Dealers Association. Last year sales declined 4.3 percent, reflecting a state economy that grew at a slower pace.

Auto dealers are still hopeful for a late-year pickup in activity, though registrations overall are still projected to fall 7.2 percent to 62,387 new cars and trucks this year. Lower new-vehicle sales follow other signs that the state's economic growth is slowing. During the last year, Hawai'i has experienced declining visitor arrivals, a drop in volume of home sales and a stabilization in home prices.

Lower new-vehicle registrations are "what we predicted a while ago," said David Rolf, executive director for the Hawaii Automobile Dealers Association. "It's sort of like everything else. All things move in a cycle."

Japanese brands gained 1.7 market share points during the first half of the year.

Meanwhile, the market share of the Big Three automakers (Ford, General Motors and Chrysler) fell 2.7 points during the first six months of this year versus the same period a year earlier. That slide is expected to level off next year as new products are introduced.

If new-vehicle registrations remain at or above the 60,000 level, it's a sign that Hawai'i's economy remains relatively strong, Rolf said. However, such an increase should only result in about 10,000 new vehicles on Hawai'i's roads as an estimated 50,000 autos are scrapped annually, according to Rolf.

"The number of vehicles on the road grows at roughly the same rate as the population increases," he said.

Reach Sean Hao at shao@honoluluadvertiser.com.