一、引言自改革开放以来,中国的经济发展取得了举世瞩目的成就。人均GDP从1978年的381元稳步快速地增长到2006年的16084元,按可比价计算,年均增长率达8.12%。同期,城乡居民的恩格尔系数也分别从57.5%和67.7%下降到35.8%和43%①。如果以日消费1美元以下为贫困人口计算 I. Introduction Since the reform and opening up, China’s economic development has made remarkable achievements. Per capita GDP increased steadily and rapidly from 381 yuan in 1978 to 16084 yuan in 2006, calculated at a comparable rate with an average annual growth rate of 8.12%. In the same period, the Engel’s coefficient of urban and rural residents also dropped from 57.5% and 67.7% to 35.8% and 43% respectively ①. If you spend less than 1 US dollars daily for the poor population calculation