Nearly every household in the country spends a sizable proportion of its income on housing. The median household allots over one-third of its income to keeping a roof over its head, and the annual expenditure of the median earner’s income on housing has increased by 35 percent since 2000.

People for the most part aren’t spending more on housing because they are buying bigger or nicer houses, although some of that obviously has taken place. But most of this growth has been driven by an increase in cost. Housing prices have grown steadily in recent decades and are nearly twice as high today as they were 25 years ago, on average—a pace that far exceeds gains in income for the average household. After a sizable retrenchment in 2008-2010, prices have nearly returned to pre-recession highs, although some regions of the country are languishing.