Prices for many materials used in glass and glazing manufacturing dropped slightly in July but are up for the year, according to the latest Producer Price Index (PPI) from the U.S. Bureau of Labor Statistics (BLS).

The monthly PPI for flat glass in the commodity category dropped 0.4 percent from the previous month, but is up 2.9 percent from July 2017. According to the BLS, the commodity classification “organizes products and services by similarity or material composition, regardless of the industry classification of the producing establishment.”

The index for flat glass manufacturing in the industry classification fell 0.9 percent from June 2018 after a short gain last month. It’s up 6.7 percent from July 2017. The industry classification measures “changes in prices received for the industry’s output sold outside the industry (that is, its net output).”

Prices for fabricated structural metal products dropped 0.8 percent from the previous month. That index, in the commodity grouping, is up 8.8 percent for the year. Ornamental and architectural metal product manufacturing, in the industry category, saw a price increase of 1.4 percent for the month, and has experienced a 10.3-percent increase since July 2017.

The PPI for metal windows rose 0.6 percent from its June level, and is up 7.7 percent from July 2017’s report. Metal doors and frames rose a modest 0.3 percent from June and are up 7 percent for the year.

The cost of builders’ hardware, which includes hardware used in doors and windows, rose 0.4 percent in July from the previous month. That price is 1.5 percent higher than in July 2017.