The World Bank has reviewed its poverty definition and calculation methodologies several times over the last 25 years. In early 1990s, The World Bank anchored absolute poverty line as $1 per day. This was revised in 1993, and the absolute poverty line was set at $1.08 a day for all countries on a purchasing power parity (PPP) basis, after adjusting for inflation to the 1993 US dollar. In 2005, after extensive studies of the cost of living across the world, The World Bank raised the measure for global poverty line to reflect the observed higher cost of living. Thereafter, the World Bank determined poverty rates from those living on less than US$1.25 per day on 2005 PPP basis, a measure that has been widely used in media and scholarly circles.