BEIJING -?Data from China's National Bureau of Statistics (NBS) on Friday showed the income gap between the country's urban and rural residents narrowed further in 2011.

The income ratio between urban and rural residents stood at 3.13:1 in 2011, meaning city dwellers' average income was 3.13 times of that for rural people. The ratio shrank from 3.23:1 in 2010 and 3.33:1 in 2009.

Rural residents' per-capita income rose 17.9 percent year-on-year in 2011 to 6,977 yuan ($1,105.71), while the per-capita disposable income of urbanites was 21,810 yuan, up 14.1 percent from one year earlier, the NBS said, citing figures from a survey of 74,000 rural households and 66,000 urban households nationwide.

The survey results showed the per-capita wage income of rural residents rose 21.9 percent to 2,963 yuan in 2011, with wages accounting for 42.5 percent of rural residents' incomes, up 1.4 percentage points from one year ago.

The NBS attributed the big increase in rural residents' wages to rising incomes of migrant workers last year. However, it also said price plunges of some farm produces such as cotton and potato caused losses for farmers.

Previous data from the NBS showed China's urban population surpassed that of rural areas for the first time in the country's history.

At the end of 2011, the country counted 690.79 million urban dwellers, up 21 million over the previous year, while the rural population shrank by 14.56 million to 656.56 million over the same period.