were fed by fixed food rations established by the central government, which declined to an average of 1500 calories per day at times but still allowed survival for almost all during the famine. An estimated 95% or higher of all deaths occurred among rural hukou holders. With the suppression of news internally, many city residents were not aware that mass deaths were occurring in the countryside at all. This was essential to preventing organized opposition to Mao's policies. Post-1978 During China's transition from state socialism to market socialism (1978-2001), migrants, most of whom were women, worked in newly created export-processing zones in city suburbs under sub-standard working conditions. There were restrictions upon the mobility of migrant workers that forced them to live precarious lives in company dormitories or shanty towns where they were exposed to abusive treatment. The impact of the hukou system upon migrant labourers became onerous in the 1980s after hundreds of millions were ejected from state corporations and cooperatives. Since the 1980s, an estimated 200 million Chinese live outside their officially registered areas and under far less eligibility to education and government services, living therefore in a condition similar in many ways to that of illegal immigrants or to black people living in "white" regions under Apartheid. The millions of peasants who have left their land remain trapped at the margins of the urban society. They are often blamed for rising crime and unemployment and under pressure from their citizens, the city governments have imposed discriminatory rules. For example, the children of farm workers () are not allowed to enroll in the city schools, and even now must live with their grandparents or other relatives to attend school in their hometowns. They are commonly referred to as the home-staying children. There are around 130 million such home-staying children, living without their parents, as reported by Chinese researchers. As rural workers provide their workforce in the urban areas, which also profit from the respective taxes, while their families use public services in the rural areas (e.g. schools for their children, health care for the elderly), the system leads to a wealth transfer to the wealthier urban regions from the poorer regions on the public sector level. Intra-family payments from the working-age members to their relatives in the rural areas counteract that to some extent. Migrant workers in cities With the loosening of restrictions on migration in the 1980s