BEIJING -- The index tracking the development of China's bulk commodity market rallied in May, industry data shows.

The China Bulk Merchandise Index stood at 100.7 percent for May, up 0.4 percentage points compared with April, according to the China Federation of Logistics and Purchasing.

A reading above 100 indicates expansion, while a reading below 100 reflects contraction.

Sub-indices measuring bulk commodity supply and inventory both rose from the previous month, while the sub-index for sales posted a consecutive decline.

The federation warned of the persistent operation pressures in the sector in June, citing factors including waning demand due to the slack season and high external risks.