The National Association of Realtors report said that existing home sales plunged 16.7 percent in Dec 2009 to a 5.45 million-unit annualized rate.
"The decline was the biggest since records began in 1968," the NAR said
The NAR report also said that sales fell as the federal government's original tax credit program expired
"This is a huge blow, much bigger than we expected," PNC senior economist Craig Thomas was quoted by media as saying.
"Unfortunately, we'll continue to see this kind of volatility as economic supports like the tax credit are taken away," he said.
According to a RealtyTrac Inc forecast on Jan 14, rising foreclosures and joblessness will weigh on housing recovery.
"A record 3 million US homes will be repossessed by lenders as unemployment and depressed home values leave borrowers unable to make mortgage payments or sell," the forecast said.
The US has lost 7.2 million jobs since the recession began in Dec 2007, and economists surveyed this month forecast the jobless rate will average 10 percent this year.