Of the countries where more than 40 percent of the population are living in extreme poverty, all but two are in Africa (Bangladesh and Haiti). Strong global growth in developing countries in particular created the conditions for the reduction by half of the proportion of extreme poor between 1990 and 2010, In a recent study of long-run growth in 118 countries, the strongest driver of poverty reduction among lowest-income earners was found to be increases in average GDP per capita, reinforcing the existing consensus on this relationship. However, both scenarios assume that the same relationship between per capita GDP growth and the decline in poverty is sustained — and there is evidence that this is unlikely. After poverty reduction reaches the majority of poor people close to the middle of national income distributions, poverty will fall more slowly for the remaining poor at the bottom of the income distribution.