December leading economic indicators up 1% (by Ruth Mantell)

WASHINGTON (MarketWatch) -- The economy's expansion is expected to continue, though there are "some strong headwinds" in the medium-term, the Conference Board said Thursday as it reported that its leading economic index rose 1% in December. "Overall, economic activity is likely to continue to gain momentum in 2011," said Ken Goldstein, economist at the Conference Board, in a statement. Six of the 10 indicators included in the LEI made positive contributions in December, led by building permits, the interest rate spread, and average weekly initial claims for unemployment-insurance benefits. In November, the LEI gained 1.1%. The LEI is a weighted gauge of 10 indicators that are designed to signal business cycle peaks and troughs. There have been widespread strengths among the indicators in recent months, according to the Conference Board. For the six months through December, the LEI gained 3.3%, up from 2.4% in the prior six months.