The disposable income of residents in 29 inland provinces, regions and municipalities including Beijing and Guangdong Province, has increased due to labor shortages and lower inflation, experts said Sunday.

China's average disposable income was 12,509 yuan for the first half of the year, growing 13.3 percent and inflation-adjusted 9.7 percent year-on-year, according to figures from the National Bureau of Statistics.

The disposable income in the majority of these provinces, regions and municipalities grew more than 10 percent in the first six months compared with the same period of last year, china.com.cn, a business news portal, reported Sunday, citing data from local statistics available at the end of last week.

Shanghai tops the list with average disposable income of 20,689 yuan ($3,242) for the first half of the year, followed by Zhejiang Province with 18,802 yuan, while Beijing ranks the third with average disposable income at 18,154 yuan.

Northwest China's Qinghai Province has the lowest half-year disposable income of residents who provided data, which stood at 7,848.41 yuan, growing by 11.6 percent for the first half of the year.

Majority of the provinces including Ningxia, Anhui, Shaanxi, Yunnan and Liaoning reported higher growth of disposable income than the national average, though their amount of the income is lower than the national average.

But many people raise doubts over such high growth in disposable income, as China's economy has been slowing. The GDP growth fell to 7.6 percent in the second quarter from 8.1 percent in the first quarter.

According to a survey conducted by business portal hexun.com, 61.54 percent of the respondents said their disposable income failed to reach the local average, and 80.7 percent believed that the income statistics are not credible.

Some provinces, such as Guangdong, reported higher rate of growth in disposable income compared with their GDP growth.

"Due to a shortage of labor, a rise in wages in many places contributed to the high growth of disposable income," Chen Naixing, a researcher with the Chinese Academy of Social Sciences, told the Global Times.

By the end of June, a total of 16 provinces and municipalities had raised the minimum monthly salary by an average 19.7 percent, said Yin Chengji, a spokesman with the Ministry of Human Resources and Social Security, on July 25.

The disposable income growth should not be as high as reported if the figures are adjusted against inflation, said Wang Xiaoguang, a researcher with the Chinese Academy of Governance.

The inflation-adjusted disposable income growth in Shanghai and Beijing is only about 8.6 percent and 8 percent respectively, according to local statistics authorities.

Lower inflation this year has strengthened consumer's purchasing power, Wang said.

China's inflation measured by consumer price index was 3.3 percent in the first six months, compared with 5.4 percent in the same period of last year, according to official statistics.