BEIJING, Sept. 5 (Xinhua) -- China's courier sector continued to expand in August, a monthly industry index showed Monday.

The China express delivery development index for August came in at 311, up 12.9 percent month on month, the State Post Bureau said in a statement.

The sub-index for the development scale grew 4.7 percent from a year earlier, and it was estimated that some 9.6 billion pieces of parcels were delivered last month.

The State Post Bureau attributed the country's courier business growth in August to the resumption of delivery services in courier hubs previously affected by COVID-19 outbreaks, the peak season for agricultural product sales, and the promotion of e-commerce platforms.

Meanwhile, the sub-index for development capacity ticked up 6.2 percent year on year, indicating China's improving express delivery network infrastructure and delivery efficiency.