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.
Poverty gap index
If you multiply a country's poverty gap index by both the poverty line and the total number of individuals in the country you get the total amount of money needed to bring the poor in the population out of extreme poverty and up to the poverty line, assuming perfect targeting of transfers. For example, suppose a country has 10 million individuals, a poverty line of $500 per year and a poverty gap index of 5%. Then an average increase of $25 per individual per year would eliminate extreme poverty. Note that $25 is 5% of the poverty line. The total increase needed to eliminate poverty is US$250 million—$25 multiplied by 10 million individuals.