BEIJING, Aug. 16 -- China's coastal bulk freight price index went down 1 percent month on month in July, data from the Shanghai Shipping Exchange (SSE) showed.

Last month, the composite price index for coastal bulk freight, which measures transportation costs in the coastal shipping market, stood at 950.75, according to the SSE.

In this period, the sub-index for refined oil saw the most notable decrease of 2.5 percent, followed by that for coal and metal ore, which fell 1.5 percent and 0.6 percent, respectively.

Bucking the trend of contraction, the price index for grain logged a 6.3-percent increase from the previous month.

The data also revealed that the sub-index for crude oil remained flat on a monthly basis in July.

The SSE initiated the index in 2001 under the guidance of the Ministry of Transport to fully reflect fluctuations in the Chinese coastal transport market.