Vox: Why the World Bank is changing the definition of the word “poor”
Charles Kenny, senior fellow, and Justin Sandefur, research fellow, both at the Center for Global Development

“…Ultimately, picking a poverty line is pretty arbitrary. The main virtue of the line the World Bank has picked is political: It keeps the total number of global poor roughly where it was last month when world leaders at the U.N. signed up to eradicate poverty by 2030. But it did so by moving the line quite a bit. In the future, it’d be nice to have a measure of poverty that doesn’t swing wildly — or necessitate a change in methodology — every time exchange rates move. But for all the uncertainty around poverty lines and numbers, and despite the fact that $1.90 is still obscenely low, one thing is certain: We do know the number of people living on $1.25 in 2005 dollars has been dropping — as has the number living on less than $1.90 in 2011 dollars. Most of the very poorest worldwide are able to buy more of what they need than they could 10 or 20 years ago. Perhaps the extreme poverty line is fuzzier than we thought, but the progress against extreme poverty remains clear” (10/7).