New Census numbers suggests the Portland area's population boom could be losing steam.

The metro area grew by just over 30,000 residents in the year that ended July 1, according to the Census Bureau. That's a population increase of about 1.2 percent, or 578 people a week -- the region's slowest growth since 2013.

That put the metro population at 2.45 million as of July 1. Portland remains the nation's 25th largest metro area, a position it has held since 2012.

The slowdown isn't unexpected. In fact, demographers say it was inevitable after three years of exceptionally strong population growth.

"It's still growing very fast, just not as fast as it was in 2015 and 2016," said Nick Chun, who coordinates forecasts at Portland State University's Population Research Center. "It's really difficult to describe how abnormal a lot of the growth is that these areas saw in those years."

The Portland metro added nearly 40,000 people each year in 2015 and 2016, according to the Census Bureau.

As the state's economy boomed in the recovery from the Great Recession, new jobs lured new residents to the state. The economy continues to grow, but more slowly, and migration has followed suit.

"We're on our way to transitioning down to something more sustainable," said Josh Lehner, a state economist. "So much of the last seven to eight years has been about putting people from the recession back to work, and we've done that. Now, with the economy starting to taper, we're expecting population growth to taper."

The slower population influx also tracks with Portland's housing market. The construction of new apartment buildings looks to be on the decline, and rents -- particularly at the high end -- have plateaued.

The median price to buy a home, meanwhile, continues to rise at rates higher than historical averages, but that growth has slowed, too.

Lehner said it will be important for officials to track the reasons for the slowdown.

"If it's about housing affordability choking off some of our growth because people can't afford to move here, then it's a problem," he said. "If we're not bringing in the influx of young people we always do, that's also a cause for concern.

Natural growth -- the population increase attributable to having more births than deaths -- has slowed in Oregon and Portland as the state's population ages. That means the state will be more reliant on new arrivals to fill out its workforce.

BEND, PRINEVILLE REMAIN BOOMTOWNS

The Bend-Redmond metro area remains one of the nation's fastest-growing, and the growth is also spilling over into nearby Prineville.

The Bend area gained 6,200 residents in a year, an increase of 3.4 percent. That's also slower than the year prior, but it's still the fourth-fastest-growing metropolitan area in U.S. on a percentage basis. The area's population now sits at 186,875.

Prineville, meanwhile, is the fourth-fastest-growing among small urban areas, with a 3.5 percent increase in population. The approximately 800 new residents bring the area's population to 23,123.

Even though the Crook County seat has lost jobs and significant employers in recent years, its seen a rise in employed residents.

"They're seeing the community become more of -- and this is going to sound like a bad word to some rural folks -- a bedroom community for places like Bend and Redmond," said Damon Runberg, the regional economist for the state's employment department.

Bend's economy, meanwhile, has grown across virtually every sector, Runberg said. The unemployment rate is historically low, and businesses are having a hard time finding employees.

"The population growth is kind of a welcome relief," Runberg said.

-- Elliot Njus

enjus@oregonian.com

503-294-5034

@enjus