China's coastal bulk freight market saw an overall increase in demand in August, according to the Shanghai Shipping Exchange (SSE).

The composite index for coastal bulk freight went up by 6.5 percent month on month to 1,040.96 in August, the SSE said.

The index had averaged 1,024.04 since the beginning of 2019, up from an average of 1,149.05 for 2018.

Last month, the sub-index for grain saw the largest jump of 9.2 percent to stand at 846.48, followed by oil products and coal, up 8.7 percent and 7.9 percent, respectively.

The sub-index for crude oil remained flat.

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