Homebuyers in the market this spring are being slammed by a 'double whammy'

US pending home sales unexpectedly slumped in April, according to the National Association of Realtors.

Pending sales of condos, co-ops, and single-family homes fell by 1.3%, worse than the 0.5% drop expected.

"Prospective buyers are feeling the double whammy this spring of inventory that's down 9.0 percent from a year ago and price appreciation that's much faster than any rise they've likely seen in their income,"said Lawrence Yun, the NAR's chief economist.

"Much of the country for the second straight month saw a pullback in pending sales as the rate of new listings continues to lag the quicker pace of homes coming off the market."

Realtors reported higher foot traffic compared to a year ago, but it's not translating to higher sales.

Pending sales are based on signed contracts that have not yet closed, so they are a leading indicator of future sales.

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Last month, the NAR said the stock market's rise and the expectation that interest rates would rise was spurring "significant interest" in homebuying. However, housing supply — especially in the more affordable lower-to-mid price range — was not keeping up with the level of demand as the market entered the busy spring season.

Yun said investors who bought single-family homes after the financial crisis to rent out are showing no intentions of selling. Rising mortgage rates could also be a constraint to inventory levels if existing home owners do not wish to trade the lower rate they've locked in for a higher one.

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