The World Bank has an amazing tool which is the window to a big database on poverty numbers. They call it PovcalNet. For almost every country, it has figures for poverty headcount ratio, poverty gap, squared poverty gap, number of poor, and total population. Both the latest and historical data are available.
There are multiple options one could choose from. Select one country and explore the historical data, or select multiple countries and do a comparison, or check out the default regional aggregation. Want to embed the database in your site? Totally possible!
Click here to explore PocvalNet.
All rights rest with The World Bank.