In the TED Talk above recorded last May, Hans Rosling examines the trends of birth rates around the world by religious affiliation, and then by country and per-capita income:

Hans Rosling had a question: Do some religions have a higher birth rate than others — and how does this affect global population growth? Speaking at the TEDxSummit in Doha, Qatar, he graphs data over time and across religions. With his trademark humor and sharp insight, Hans reaches a surprising conclusion on world fertility rates.

The lecture is very engaging and is worth a view, particularly in light of the implications around public health policy.