Good data can inspire confidence in poverty reduction plans and ensure spending decisions are backed with evidence. Weak or absent data reduce the goal of poverty reduction to a matter of faith.
Data are relied on to determine the prevalence of poverty and its characteristics, to quantify and allocate global resources devoted to reducing poverty, and to assess whether investments to help the poor ultimately work.
This paper focuses on the methods used to calculate the number of people living in poverty around the world. It describes various problems encountered in working out global poverty estimates, and their implications in terms of the accuracy and application of poverty data.