Even middle classes dissatisfied with income distribution The mainland's richest people are earning on average about 18 times more than its poorest, and most mainlanders see themselves as being on the lower rungs of the income ladder, reports by a leading government think-tank show. In a yearbook on China's social development released yesterday, the Chinese Academy of Social Sciences said China's Gini coefficient - a measure of income distribution inequality - rose to 0.496 this year, up from the 0.47 World Bank assessment for last year. A coefficient higher than 0.4 is normally a warning sign of social unrest. Li Peilin , dean of the academy's sociology institute, said the widening income gap could be attributed to a growing gulf in earnings between western regions and those in the more prosperous east, between farmers and farmers-turned-migrant workers, and between employees in state monopolies and sectors open to free competition. In a national survey between March and July, academy researchers asked people to identify their economic and social status. Of the 7,063 families questioned 29.1 per cent ranked themselves in the lower-middle category while more than 24 per cent put themselves in the lowest socio-economic class. The 54 per cent total for the two lowest rungs was higher than the 41 per cent registered in the previous survey four years ago. 'The prevalence of [people identifying themselves as low ranking] shows that in this rapidly changing society, income distribution problems have meant that not only low-income families are discontent. Some middle- and medium-to-upper-level ones are also dissatisfied,' the report said. To determine the greatest source of perceived inequality in terms of social status, researchers listed seven pairs of social groups and asked respondents to choose the one that was the most imbalanced and the one with the greatest conflict. The groups were the poor and the rich, cadres and the masses, urban and rural residents, employers and employees, managers and the managed, the well educated and the low educated, and knowledge workers and physical labourers. Around 50 per cent of respondents thought the gap between poor and the rich was the biggest and the greatest conflict was seen as that between cadres and the masses. Social security had become the public's greatest concern, ahead of employment, the environment and crime, another academy quality-of-life survey found. Yuan Yue , the president of the Horizon Research Consultancy Group which carried out some of the research for the two reports, said: 'Residents are more worried about pensions and medical care, especially since Shanghai's social security fund embezzlement scandal.'