BEIJING -- A slump in China's railway freight volume, an indicator of economic activity, picked up pace in October, the country's top economic planner revealed on Wednesday.

The railways carried 280 million tons of cargo in October, down 16.3 percent year-on-year, compared with a fall of 15.6 percent in September and 15.3 percent in August, according to data released by the National Development and Reform Commission (NDRC).

In the first 10 months of 2015, rail freight slipped 11.9 percent from a year earlier to 2.8 billion tons, a sharper decline than the 11.4-percent decrease for the first nine months, the NDRC said.

The figures came as China's inflation indicators continued to fall, showing that demand remains weak in the world's second-largest economy.

The consumer price index (CPI), the main gauge of inflation, grew 1.3 percent year-on-year in October, slower than a 1.6-percent gain in September, official data showed. The producer price index (PPI), a measure of costs for goods at the factory gate, dropped 5.9 percent year-on-year.

China's economy has slowed as a result of cooling property investment, a prolonged industrial glut and sagging trade. Its GDP expanded 6.9 percent year-on-year in the third quarter of 2015, the lowest reading since the second quarter of 2009.