South Korea's producer prices dropped slightly from a year earlier in July on a large cut in prices of coal and petroleum products, central bank data showed Friday.

The producer price index for July came to 98.95, down 2.4 percent from the same month last year, according to preliminary data from the Bank of Korea.

Producer prices serve as an indicator of future consumer inflation.

The July index marked a slight decrease from a revised 99.02 in the previous month.

Prices of manufactured goods lost 0.1 percent on-month in July, while prices of agricultural and fisheries goods gained 0.6 percent on-month in July.

Utility prices, including electricity and water, dropped 2 percent from the previous month, according to the BOK. (Yonhap)