BEIJING -- China's retail sales grew 12.9 percent year on year to 16.88 trillion yuan ($2.75 trillion) in the first three quarters of this year, the National Bureau of Statistics (NBS) said Friday.

Total retail sales in September hit 2.07 trillion yuan, up 13.3 percent over the same period last year, and down slightly from the 13.4-percent growth registered in August, the NBS data showed.

NBS spokesman Sheng Laiyun cited the large comparative base of last September as reason for the slowing growth, noting that month-on-month growth for this September reached 1.24 percent.

Urban consumption hit 1.76 trillion yuan in September, up 13.1 percent year on year, while rural residents spent 304.7 billion yuan, up 14.8 percent from the previous year.

The catering sector reported 225.9 billion yuan in revenues in September, up 9.1 percent year on year. The retail goods trade was valued at 1.84 trillion yuan, up 13.9 percent.

The average salary for urban residents stood at 22,068 yuan in the first three quarters, up 9.5 percent year on year. The figure for rural residents rose by 12.5 percent year on year to 7627 yuan.

China's GDP growth accelerated to 7.8 percent in the third quarter, up from 7.5 percent in the second quarter, the NBS data showed.