Flat glass prices dipped .6 percent from December to January, marking the fourth such fall in prices within the last five months, according to the latest Producer Price Index (PPI) Report issued by the U.S. Labor Department.

The only increase came from October to November, when the prices of flat glass rose 1.3 percent. The overall price of flat glass, however, remains 1.5 percent ahead of where it was a year ago in January 2013.

The report also showed incremental increases from December to January in new office building construction (.6 percent), new industrial building construction (.5 percent) and new health care building construction (.4 percent).

The overall PPI for final demand increased .2 percent in January when seasonally adjusted, government statistics says. The advance follows a decrease of .1 percent in December and no change in November. On an adjusted basis, the index for final demand climbed 1.2 percent for the 12 months that ended in January.

In related news, the U.S. Bureau of Labor Statistics reported that American import prices rose for the second consecutive month. The .1 percent advance in January comes on the heels of a .2 percent decrease in December.

Both the import and export prices of glass and glassware rose in December and remain higher now than they were a year ago, according to the report. Import prices for glass and glassware climbed .5 percent from December to January, and remain .9 percent higher than this same time last year. Export prices for glass and glassware grew at a smaller rate, advancing .2 percent between December and January and .5 percent over the last 12 months.