Update: Metro Grand Rapids, swelling to 1M people, leads Michigan metros in growth; read more figures

GRAND RAPIDS, MI — Metro Grand Rapids as we know it has morphed to include more than 1 million residents for the first time under new designations released this week by the U.S. Census Bureau.

Bolstered in part by shifts in the state's population over the last decade, but mostly by force of a federal formula, the new Grand Rapids-Wyoming metro area includes 1,005,648 people across Kent, Ottawa, Montcalm and Barry counties.

That's a marked increase from 774,160 people in the now-defunct metro area that included Kent, Ionia, Barry and Newaygo counties, and a figure that is expected to boost the area's visibility to corporations and other key groups.

Related: New Census numbers: Michigan's population finally grows; see which counties are on upswing (database)

"That's probably the biggest thing," state demographer Kenneth Darga said, of the potentially heightened visibility of metro Grand Rapids on a national level.

The new designation makes Grand Rapids the 52nd largest metro area in the nation. It maintains its spot as second largest in Michigan, behind the Detroit-Warren-Dearborn metropolitan area.

Population statistics for the new and old Grand Rapids-Wyoming metropolitan areas, according to U.S. Census figures.

"If a business is looking for a place to locate a new project, they might look at metros with over a million people, so Grand Rapids meets that criteria," Darga said.

Metro designations are derived from commuting data gathered by the federal Census Bureau. Kent County, by virtue of Grand Rapids' urban population, is ostensibly designated as a "central county."

To qualify as "outlying," 25 percent of an adjacent county's workforce must commute to the central county, Darga said. In this case, 25.6 percent commute from Ottawa County, 26.2 percent commute from Montcalm and 25.1 percent from Barry.

The less populous Ionia and Newaygo counties no longer meet the commuting threshold, and they no longer are considered part of metro Grand Rapids.

Census data show Kent County's population increased to 614,462 in 2012, a 1.05 percent increase over 2011. Ottawa County's population grew by 1.1 percent, to 269,099. That county's inclusion in the metro area helped push its population past the 1 million mark.

Montcalm County's population dipped a marginal .22 percent, to 63,097 people. Barry County's population grew by a small amount, to 58,990, or plus .09 percent.

Notably, the four counties are included in the vast, and more overlooked, Grand Rapids-Wyoming combined statistical area, which includes eight counties and nearly 1.4 million people.

Combined statistical areas are a consolidation of nearby metropolitan and micropolitan areas, Darga said.

In this case, metro Grand Rapids is combined with Muskegon, Allegan, Mecosta and Ionia counties to form the eight-county combined statistical area.

Despite the gains, Darga warned that basing the formula on commuting data opens the possibility of a drastically reduced or altered metro Grand Rapids area over the next decade.

Because commuting rates from Ottawa, Barry and Montcalm counties are so near the 25 percent threshold, even small decreases in commuting by 2023 could greatly reduce the Grand Rapids-Wyoming metro area.

For at least the next decade, though, metro Grand Rapids will be four counties with populations that by and large have grown over the last several years.

"West Michigan is very unstable with the current methodology, because there are so many counties where the commuting rate is insignificant from 25 percent," Darga said. "The Grand Rapids metro could be anywhere from one county to nine counties."

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