DENVER (KDVR) — Denver has one of the nation’s highest shortages of housing, according to a new report from Zillow. The report pinpoints how many housing units each of the 100 largest U.S. cities needs in order for families to afford homes appropriate for their situations.

The number of families in the U.S. has grown far faster than the rate at which new homes are being built. Between 2015 and 2021, there were 6.3 million new housing units built. However, the number of families and new households grew even more.

The Great Recession put a sudden stop to the housing construction wave that was happening into the 2000s, but there are other factors that tighten the housing supply even further.

Over 10 million homes could be occupied, but are instead simply sitting vacant. There were 15.6 million vacant homes in 2021, but only 3.7 million of them were available for rent or for sale.

Between the lack of construction and the presence of unavailable vacant housing units, some cities have housing shortages in the hundreds of thousands of units.

Denver has one of the nation’s worst housing shortages. Colorado’s capital is missing 70,000 units, the nation’s 13th-highest shortage.

Nearby, Colorado Springs doesn’t have quite the same size of a shortage but is still missing 18,000 units.