Commercial building construction costs increased 4.9 percent over the past year, according to Turner Construction Co.

During the fourth quarter, material and energy prices declined but labor costs went up, causing construction costs to stay flat. That caused the Turner Building Cost Index to remain the same as in the third quarter.

The index is determined by several nationwide factors, including labor rates, productivity, material prices and the competitive condition of the marketplace.

There has been a global drop in steel, copper and aluminum prices, declining energy prices and a slower pace of construction starts. Competition for small-scale projects has gone up.

“The decline in commodity and material costs is largely being offset by rising labor costs which is resulting in construction costs remaining steady,” said Karl F. Almstead, vice president at Turner.

Turner has prepared the construction cost index for more than 80 years. It is used widely by the construction industry and federal and state governments.

Based in New York City, Turner is the one of the biggest commercial builders in the U.S. The company has an office in Albany, N.Y.