Madison home construction.JPG
A home is shown under construction in Madison, Ala., in this 2012 file photo. Madison County added housing units at one of the fastest rates in the nation between 2010 and 2014. (AL.com file photo).
Two Alabama counties, Russell and Madison, were among the 100 U.S. counties with the highest rates of increase in housing units between 2010 and the middle of last year, the U.S. Census Bureau reported Thursday.
Changes in a county's housing stock often serve as a strong indicator of population growth, and indeed, the counties that saw increases of 2 percent or more in the number of housing units since the last census year in 2010 mostly are at the top of the list for population growth.
Russell County, along the Georgia border, increased its housing stock by 2,195 units from 2010 to 2014, an 8.9 percent increase that ranked it No. 31 in the country among counties with at least 5,000 units. At 12.6 percent, Russell also has led the state in population growth during that period.
Madison County added 8,005 housing units - the most in Alabama - to reach 154,452 as of July 1, 2014. Its 5.5 percent growth rate was good for 93rd place in the nation. Its population growth during that period was sixth-most in Alabama, strong but not quite at the rate of its housing growth.
Although the two are related, experts said housing growth is not the same thing as population growth.
"You cannot ever say how much population grows because of housing units," said Viktoria Riiman, a researcher with the University of Alabama's Center for Business and Economic Research. "It's basically inventory."
In Baldwin County, the population grew more than three times as fast as the number of housing units. In Limestone County, population increased nearly 7.5 times as fast. In Lee County, the population increase nearly twice as fast.
Some counties saw the inverse. In Pike County, for instance, the number of housing units increased at more than double the rate of the population increase. Mobile County increased its housing stock by nearly 2 percent despite the fact that the population edged up by just a half a percent. Jefferson County's housing units increased at nearly four times the rate of its anemic population growth.
In Montgomery County, the number of housing units jumped by 1.8 percent, even though the population declined by 1.4 percent.
"Housing can increase in anticipation of a population increase," Riiman said. "Its population can be lagging."
Many of Alabama's shrinking counties are not just losing people, they're losing housing, as well. There were 1 percent fewer housing units in both Lowndes and Perry counties in July 2014 than during the 2010 census. Forty-one counties, overall, lost housing during that period.
The Census Bureau counts a housing unit as lost if it has been demolished, if the interior has been exposed to the elements or if a house or mobile home has been moved to another county.
"You'd be surprised," Riiman said. "Some homes do move."