This Great Graphic was tweeted by Justin Sabdefur, who noted that the percentage of the world's population that was impoverished in 2000 was roughly the same as the percentage of poor in the US in 1860.  He found it in this 300-page study about poverty by the World Bank.  

Yes, there are definitional and methodological issues. Yet it is profound on several different levels.  

First, poverty is partly a historical creation. There have always been poor people, but in other epochs the Church would provide sustenance and shelter. During feudalism, the lord could not simply kick out the serfs. There were reciprocal rights and responsibilities.

Second, by the definition of poverty used here, the high income countries have made huge strides in ending it. Ironically, most of the reduction in poverty took place amid great disparities of wealth and income. 

Thirdly, there is a hint here of a concept that we think is under-appreciated by many economists. It is uneven development. Some countries have proceeded from agriculture to manufacturing to services at different speeds and in different ways. Recognizing that were countries rapidly industrialized, the environment was damaged. Many people who talk about the Beijing sky, for example, seem not to appreciate that London was once like that, as was Pittsburgh, for example. Given China's per capita income (~$6800 per year), that it has begun to think about the environment is notable. That is the story.That its rapid industrialization showed little concern for what economists call "externalities" (unintended consequences of its main pursuit) is a dog bites man story. 

Fourth, world poverty, according to the definition employed here, is falling. over the past half century is not so much a function of the high income countries.   China's economic progress has had much to do with the last 35 years.   So has Indian and African growth.  We have the means to end poverty.  Will it take another century?