Statistically, most of this decline has been due to the rapid growth of China. Several factors played a role in this, particularly declining incomes in Latin America during the Tost decade’ of the 1980s and the prolonged economic implosion of countries in sub-Saharan Africa, as well as the economic collapse of transition countries in the late 1980s and 1990s. Accessed between 15 and 30 July 2012, and World Population Prospects: The 2010 Revision.