The National Association of Home Builders says its housing market index slipped in December, reflecting concern that job losses will continue to stifle demand for new homes despite the extension of a homebuyer tax credit.

The Washington-based trade association said Tuesday its index fell one point to 16, the lowest since June.

Readings below 50 indicate negative sentiment about the market. The last time the index was above 50 was in April 2006.

The report reflects a survey of 514 residential developers nationwide.

The reading for current sales conditions slipped one point to 16. Traffic by prospective buyers held steady at 13. The index for sales expectations over the next six months fell two points to 26.