Sales dropped to the lowest number on record since the government started keeping track in 1963.

Sales of newly built, single-family homes dropped precipitously in May following the April 30 expiration of the home buyer tax credit program, the U.S. Commerce Department said.

Sales dropped 32.7 percent to a seasonally adjusted annual rate of 300,000 units, the lowest number on record since the government started keeping track in 1963.

"While today's numbers are sobering, they were to be expected at the conclusion of the tax credit program and are in keeping with the results of our latest home builder surveys," said Bob Jones of Bloomfield Hills, Mich., chairman of the National Association of Home Builders. "Clearly the tax credits were very successful in drawing potential buyers back to the market. Now we are seeing the lull in activity you'd expect following the program's expiration."