Posted on 03 May 2022
Since the introduction of the dollar-a-day poverty line in the 1990 World Development Report, the World Bank has used purchasing power parities (PPPs) — exchange rates that account for relative price differences across countries — to derive the international poverty line and estimate global poverty.
The international poverty line increases over time primarily because prices tend to increase. As a result, the international poverty line will be $2.15. This means that everyone living on less than this amount per day will be considered in extreme poverty.
See the World Bank fact sheet here for a full explanation.