The study, compiled by School of City and Regional Planning professor Dan Immergluck, says the metro area has been experiencing an apartment boom since the recession. As of March, there were 11,000 units under construction and another 9,000 proposed, according to cited research from Haddow and Co.

But those units, Immergluck writes, are almost entirely luxury rentals, with rents hovering around $2 or more per square foot. Meanwhile, rentals for $750 a month or less are disappearing. The Tech professor estimates these low-cost units were lost at a rate of about 4.4 percent annually between 2010 and 2013, a dip of about 1,600 each year.

Read Immerglcuk's report on the WABE site.