Extreme poverty, as defined by the World Bank, meant not having enough income to meet the basic human needs for adequate food, water, shelter, clothing. sanitation, health care or education 2008, the Bank calculated that this requires a daily income that is the purchasing power equivalent of about USD 1.25 per day in the United States. That is not the foreign exchange equivalent of USD 1.25, which might not be so bad, because as everyone who travels from a rich country to a poor cr knows, the currencies of rich countries often have much greater purchasing power in poor countrie The World Bank's definition takes that difference into account: the poor earn only as much as buy, in their currency, the quantity of necessities the USD 1.25 will buy in the United States. Thr Bank estimates that 1.4 billion people have less income than this.