Here’s a an insightful video explaining how the world has changed with respect to economy & population. Hans Rosling presents very important data in a ‘non-boring’ manner. I wish more professors were like him.

Watch this and be informed. The world has changed in ways that can surprise you and the data presented will be a good picture of the changes over the last 3 decades or so.

By the way, there is a correlation between family size, life expectancy & income.