Construction input prices dipped 1.4 percent in December and are down nearly 1 percent on a year-over-year basis, according to the recently released producer price index report from the U.S. Department of Labor.

Inputs to nonresidential construction fell further, down 1.7 percent for the month and 1.9 percent year over year. December’s report marks the sharpest decline in input prices since late 2008 during the global financial crisis and the fifth consecutive month construction materials prices have failed to rise, according to the Associated Builders and Contractors (ABC).

“Without question, financial markets have been unnerved by the recent declines in oil, copper and other commodity prices, although that jitteriness does not necessarily imply a serious economic problem in America,” says ABC chief economist Anirban Basu. “The fact is the U.S. economy has performed handsomely over the past nine months, according to most metrics, and conventional wisdom suggests that it can continue to expand at or above trend rates of growth despite economic weakening in Europe, China and elsewhere. This is further evidenced by the World Bank’s recent downgrade of its forecasts for global growth in 2015 and 2016, while it upgraded its outlook for the United States.”

Seven of the 11 key construction inputs didn’t experience price increases for the month, including those of iron and steel, which fell 1 percent in December and are down 3.9 percent from the same time last year. However, four inputs saw increases, including fabricated structural metal product prices, which grew 0.3 for the month and have expanded 1.5 percent on a year-over-year basis.

“Overall, the view that U.S. domestic demand for construction services and most other services continues to expand is consistent with the fact that some domestically produced and consumed materials actually registered price increases last month,” says Basu.