And of those affordable rentals, just 11 are "naturally affordable" — or affordable without federal subsidies.
The institute used Census data from 2010 to 2014 for its calculations, so the picture could be even more stark today. But the figures serve to put into greater perspective the scarcity of affordable units on Oahu.
In fact, the report found, there's not a single county in the nation without a gap between the number of affordable units and how many are actually needed.
Among the nation's largest 100 counties, Oahu ranked 37th for the size of that gap. Hidalgo, Texas had the smallest gap, with 71 affordable rentals for every 100 low-income renters.
The largest gap was found in Gwinnett, Ga. The county has just 14 affordable units per 100 low-income renters.
Meanwhile, the study found that the number of affordable units in Honolulu from 2000 to 2014 has decreased. (Seventeen years ago, there were about 44 affordable units for every 100 low-income renters.)
In the study, a renter who is extremely low-income is defined as someone who earned 0 to 30 percent of area median income.