based on National Income Dynamics Study (NIDS) data suggests that 47% of South Africans live below the poverty line: 56% of blacks live in poverty compared to 2% of whites, using an arbitrary income poverty line of R502 per capita. Although, it should also be noted that black South Africans make up the majority of the population at 79.2% while white South Africans make up only 8.9% of the population according to the Statistics South Africa census released in 2011. The United Nations Development Program's Human Development Index (HDI) ranked South Africa 110 out of 169 countries in 2010. The report notes, however, that the region's assessment has improved slowly since 1980. The HDI includes a Human Poverty Index (HPI-1), which ranked South Africa 85 out of 135 countries. The number of South Africans living below the poverty line, identified according to Apartheid-era social categories, was calculated in one study as 56% "black", 27% "coloured", 9% "Indian", and 2% "white". In the past inequality in South Africa was largely defined along race lines, but it has become increasingly defined by inequality within population groups as the gap between rich and poor within each group has increased substantially. The Organisation for Economic Co-operation and Development proposals for addressing income inequality included: encouraging more saving and investment; a liberalisation of product-market regulation; easier access to credit for small businesses; greater co-ordination in wage bargaining; and measures to tackle the high level of youth unemployment. Some proposals have included wage subsidies for people being trained, a minimum wage differentiated by age, and extended periods of probation for young workers. In post-Apartheid South Africa, only Asians have made significant strides in closing the income gap with Whites; while Coloured and Black South Africans have had much more muted progress. A 2011 study published by the University of Cape Town about the richest 10% found that nearly 40% are black, where this group had once been almost exclusively white. While only 29% of the absolute wealthiest South Africans are black, this jumps to 50% among the "entry-level" rich (defined as earning more than $4,000 per month). Factors that were found to be common among those in the entry-level rich group include being young, entrepreneurial and having some post-secondary education. According to one estimate, 10.4% of South Africans belonged to the "higher middle class" in 2004, defined as having a per capita income of over R40,000