The gap between the capital's highest- and lowest-paid workers widened by almost 13,000 yuan in just three years, according to new statistics.

A survey of employees across 17 industries by researchers at the Beijing Academy of Social Sciences found the income divide stretched from 26,818 yuan in 2006 to 39,087 yuan in 2009.

The figures, published last Friday in the 2011 Society Blue Book, show that roughly 70 percent of workers made no more than 30,000 yuan in 2009, with almost 3 percent making less than 12,000 yuan. By contrast, the latest Hurun Report in April estimated that Beijing is home to 170,000 multimillionaires and 10,000 billionaires, the highest concentration in the country.