China's current mainly market economy features a high degree of income inequality. According to the Asian Development Bank Institute, “before China implemented reform and opening-up policies in 1978, its income distribution pattern was characterized as egalitarian in all aspects.” At this time, the Gini coefficient for rural – urban inequality was only 0.16. As of 2012, the official Gini coefficient in China was 0.474, although that number has been disputed by scholars who “suggest China’s inequality is actually far greater.” A study published in the PNAS estimated that China's Gini coefficient increased from 0.30 to 0.55 between 1980 and 2002. History In a landmark paper published in the Review of Development Economics, economists Ravi Kanbur and Xiaobo Zhang conclude that there have been three peaks of inequality in China in the last fifty years, “coinciding with the Great Famine of the late 1950s, the Cultural Revolution of the late 1960s and 1970s, and finally the period of openness and global integration in the late 1990s.” Their research indicates that these periods of inequality are driven by “three key policy variables – the ratio of heavy industry to gross output value, the degree of decentralization, and the degree of openness.” The study finds that the “heavy-industry development strategy played a key role in forming the enormous rural-urban gap in the pre-reform period, while openness and decentralization contributed to the rapid increase in inland-coastal disparity in the reform period of the 1980s and 90s.” In other words, heavy industry development in the cities formed the initial rural-urban gap leading up to the reform period, and decentralization increased overall inequality, rural-urban inequality, and inland-coastal inequality as the economy opened up after the 1978 economic reforms. Research conducted by Jeffrey Sachs on the entire period from 1952 to 1996 indicates that in general, regional income inequalities are driven by government policy, whereas income divergence is "strongly associated with the extent of marketization and openness." Current state China is a newly industrialized country and an emerging economy, with quarterly GDP growth rates averaging 9.31% for the past two decades, powered mainly by strong exports. However, China still faces a number of socioeconomic issues, including the increasing income disparity between different groups of citizens, largely characterized by rural-urban income inequality. Despite steady growth of China's economy since economic reforms in 1978, the rural-urban income gap reached its widest in more than three decades in 2009. According