Dive Brief:

• More than 70% of homes for sale have been on the market for over a month, according to a new survey by Redfin.

• Known as “stale” inventory, those unsold homes most likely are overpriced, in need of renovations, or have other problems that prevent them from selling, the study said.

• “Fresh” inventory—homes just coming onto the market—rose 9.2% in March, increasing the total number of unsold homes by 5.3%, Redfin said. At the current pace of sales, that inventory will be exhausted in 4.6 months.

Dive Insight:

The high number of “stale” homes on the market means housing inventory is tighter than previously thought. “Take the quality of inventory into account and the picture looks bleak for buyers in many cities,” the Redfin report concluded.

Redfin attributed the lack of inventory to the high number of "underwater" homeowners who are unable to sell their houses because they owe more on their mortgages than their homes are worth. The unexpectedly poor showing of housing starts last month could also be contributing to the problem.