A?housing figure used by the country's statistics agency to calculate the cost of living for Chinese people has come under criticism for being unrealistic.

The National Bureau of Statistics said in a recent report that Chinese mainland residents spent on average 111 yuan (US$17) a month on housing per capita in 2010.

This was lower than the 400 yuan spent on food, 165 yuan on transport and telecommunication, 136 yuan on education and entertainment and 120 yuan on clothing.

These figures have recently been adopted by the Ministry of Finance and the State Administration of Taxation to calculate how much Chinese people usually spend to cover basic living costs.

The new method of calculation has been introduced at a time when central government is set to raise the monthly personal income tax threshold to 3,000 yuan to relieve the burden on low and middle income groups.

Many people, including some lawmakers, argue that this threshold is still too low and have called for an increase to 5,000 yuan before tax is deducted.

"The monthly cost of living worked out by the government contrasts sharply with what most people really experience at the moment," said Liang Junjiao, a professor at Central University of Finance and Economics in Beijing. "Regardless of the figure itself, the fact that housing expenditure is lower than food, transportation and clothing seems unacceptable."

Housing costs have already become many Chinese people's single largest living expense, Liang added.

However, the statistics bureau said the housing costs it refers to mainly cover house maintenance, depreciation and management fees.

Sheng Laiyun, a spokesman for the bureau, said earlier that "rentals" used in the country's statistics reports are a different concept from the one that people usually talk about.

They are fixed numbers calculated on the basis of a property's depreciation, while in reality, home rentals always fluctuate in accordance with supply and demand.

Instead of working out a "one-fix-all" income tax threshold for the country's wage earners, Liang said the government should consider alternatives to make future taxation schemes fairer. Real housing expenses could be excluded from final taxable income, Liang suggested.