Poverty
The poverty line threshold of $1.90 per day, as set by the World Bank, is controversial. Each nation has its own threshold for absolute poverty line; in the United States, for example, the absolute poverty line was US$15.15 per day in 2010 (US$22,000 per year for a family of four), while in India it was US$1.0 per day and in China the absolute poverty line was US$0.55 per day, each on PPP basis in 2010. These different poverty lines make data comparison between each nation's official reports qualitatively difficult. Some scholars argue that the World Bank method sets the bar too high, others argue it is low. Still others suggest that poverty line misleads as it measures everyone below the poverty line the same, when in reality someone living on $1.20 per day is in a different state of poverty than someone living on $0.20 per day. In other words, the depth and intensity of poverty varies across the world and in any regional populations, and $1.25 per day poverty line and head counts are inadequate measures.
Measuring poverty
The World Bank defines poverty in absolute terms. The bank defines "extreme poverty" as living on less than US$1.90 per day> (PPP), and "moderate poverty" as less than $3.10 a day. It has been estimated that in 2008, 1.4 billion people had consumption levels below US$1.25 a day and 2.7 billion lived on less than $2 a day. The proportion of the developing world's population living in extreme economic poverty has fallen from 28 percent in 1990 to 21 percent in 2001. Much of the improvement has occurred in East and South Asia. In Sub-Saharan Africa GDP/capita shrank with 14 percent, and extreme poverty increased from 41 percent in 1981 to 46 percent in 2001. Other regions have seen little or no change. In the early 1990s the transition economies of Europe and Central Asia experienced a sharp drop in income. Poverty rates rose to 6 percent at the end of the decade before beginning to recede. There are criticisms of these measurements.