The collapse of the housing market last decade sent millions of Americans into the rental market.

That put upward pressure on rents, creating a trauma of its own.

"We are in the midst of the worst rental affordability crisis that this country has known," Shaun Donovan, Secretary of Housing and Urban Development, said at a conference Monday, CNBC reports.

Editor’s Note: Obama’s Budget Takes Aim at Retired Americans

"Over four years, a 43 percent increase in the number of Americans with worst-case housing needs. Let's be clear what that means, they're paying more than half of every dollar they earn for housing."

Half of Americans renting their homes devote more than 30 percent of their income to rent, soaring from 18 percent 10 years ago, a decade ago, according to Harvard's Joint Center for Housing Studies, CNBC reports.

The number of renter households now totals 43 million, or 35 percent of all U.S. households, according to the center. That's the highest rate in more than 10 years.

For people in the 25- to 54-year-old bracket, the rental rate is at its highest level since the center began tracking in the early 1970s.

Things are hardest, of course, for those at the bottom of the income totem pole.

"These are the people with the fewest financial resources," Sheila Crowley, president of the National Low Income Housing Coalition, a research and advocacy group, tells The New York Times. "These are the people in danger of becoming homeless."

Editor’s Note: Obama’s Budget Takes Aim at Retired Americans

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