There are currently two billion children in the world. How many will there be 100 years from now? Will that number go up, down, or stay the same, and why? In the video below, Hans Rosling takes a look at the data and the roles that religion and economics play in population change. This is one of the most interesting and entertaining TED talks I've seen in a long time, and I guarantee that the conclusions will surprise many of you.

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