Some time, when I have a bit more time, I need to write a post on the composition and meaning of global poverty data, but this (page 12 of a large PDF) is staggering regardless of the details of data composition.
One billion people live on less than $1 a day, the threshold defined by the international community as constituting extreme poverty, below which survival is questionable. That number encompasses a multitude of people living in varying degrees of poverty—all of them poor, but some even more desperately poor than others. To better answer the question of whether the very poorest are being reached, we first divided the population living on less than $1 a day into three categories according to the depth of their poverty:Remember what that 50c a day line really means is: lived off ( so consumed as opposed to earned) less each day than 54c could have brought you in the United States in 1992.
• Subjacent poor: those living on between $0.75 and $1 a day
• Medial poor: those living on between $0.50 and $0.75 a day
• Ultra poor: those living on less than $0.50 a day
This allowed us to look below the dollara-day poverty line to determine who the
poorest people are, where they live, and how each group has fared over time. We found that 162 million people live in ultra poverty on less than 50 cents a day. This is a significant number of people: if all of the ultra poor were concentrated in a single nation, it would be the world’s seventh most populous country after China, India, the United States, Indonesia, Brazil, and Pakistan.
As it is, the ultra poor are overwhelmingly concentrated in one region—Sub-Saharan
Africa is home to more than three-quarters of the world’s ultra poor. Sub-Saharan Africa is also the only region in the world in which there are more ultra poor than medial or subjacent poor. In contrast, most of Asia’s poor live just below the dollar-a-day line; only a small minority of the population is ultra poor.