Shi Shenwei works as a construction worker. [Photo/VCG]

DATA ON AN employment exchange website show the average monthly income of construction workers in Chengdu, Sichuan province, was 8,300 yuan ($1,210) last year, with skilled bar benders, bricklayers, carpenters and painters earning more than 10,000 yuan. In contrast, the average monthly salary of clerks and secretaries was about 3,800 yuan. An article on youth.cn comments:

The huge income gap between blue-collar and white-collar workers may be surprising for many people. But manual workers' incomes have been rising over the past few years because of the supply-demand law.

Each year, 7 million college graduates enter the job market, while the number of skilled laborers joining the workforce is much lower, because it takes years for a worker to become an expert in his/her field while clerks can learn their job in months.

The demand for skilled workers is high because of the boom in the infrastructure, interior decoration and service sectors. Besides, most of the skilled workers are migrants, who get fewer social welfare benefits than while-collar workers. To some extent, their relatively high income includes the compensation for that.

Those people surprised at the "decline" in the incomes of clerks and secretaries should understand the division of labor today, as the advancement of technology has divided white-collar as well as blue-collar jobs into more categories. So we should stop comparing the incomes of white-collar and blue-collar workers.