Flat glass prices increased—but barely—in July, up just 0.1 percent after a 1-percent increase over the previous two months, according to the latest Producer Price Index (PPI) released by the Bureau of Labor Statistics.

Material prices are up 4.8 percent from July 2015, the lowest year-over-year increase since September 2015.

According to the Bureau, the PPI program measures the average change over time in the selling prices received by domestic producers for their output. The prices included in the PPI are from the first commercial transaction for many products and some services.

July’s flat glass index represented its fifth month-over-month increase in 2016. The current index sits at 132.3.

Final demand for construction dropped 0.6 percent in July, but its index is still up 0.8 percent from a year ago.

Construction materials prices increased 0.4 percent after inching up 0.2 percent the month before. Those prices are up 1 percent from July 2015.

Prices for construction machinery and equipment were unchanged for the second straight month in July and have increased 0.9 percent from a year ago.

In another report, import prices for glass and glassware decreased 0.1 percent and are up 0.2 percent from last year. Export prices in that category stayed flat for the month but are up 0.8 percent from July 2015.

Overall, the PPI for final demand in the U.S. decreased 0.4 percent in July. Final demand prices rose 0.5 percent in June. On an unadjusted basis, the final demand index dipped 0.2 percent for the 12 months ended in July.

The price index for U.S. imports rose 0.1 percent in July after a 0.6-percent increase in June. U.S. export prices increased 0.2 percent in July after a 2.4-percent advance the previous three months.