Absolute poverty is defined as living on the equivalent of US$2 a day or less. In 2002, 43% of the world population lived on this little. This money has to cover the basics of food, shelter and water. Medicines, new clothing, and school books would not be on the priority list.
When almost an entire population lives on this little, it is unsurprising if undernourishment is high, education levels are low, and life expectancy short. In both Nigeria and Mali, 9 of every ten people survives on less than US$2 a day.
South America has a relatively small poor population, yet 39 million people have less than US$2 a day in Brazil.
The Earthbound Report 