China's railway freight volume grew steadily in the first half of the year, adding to signs of robust economic activity.

Rail freight rose 15.3 percent year on year in the January-June period to 1.82 billion tonnes, the National Development and Reform Commission said Friday.

In June, the volume increased 16.3 percent, an 11th consecutive monthly rise.

Rail freight, electricity consumption and lending are important indicators of economic strength. China's rail freight returned to a gaining streak last August after a six-month decline. Overall, it fell 0.8 percent year on year in 2016.

The country posted forecast-beating economic growth in H1, with GDP at6.9 percent.