Sales of new single-family homes declined 21 percent in September to an annual rate of 503,000 units from 638,000 units in the year-earlier period, the Commerce Department said Tuesday.

During the first nine months of the year, sales fell 15 percent to an annual rate of 435,000 new homes, compared with 512,000 units for the same period the year before.The department said the median sales price of new homes was $115,000 in September while the average price was $142,300.

At the end of September, the seasonally adjusted estimates of new houses for sale was 337,000, or an 8.4 month supply.

Sales were down in all regions of the nation, with the greatest monthly decline posted in the Northeast. Home sales in that region fell 15.6 percent from August to September and were 12 percent below year-ago levels.