View full lesson: http://ed.ted.com/lessons/population-pyramids-powerful-predictors-of-the-future-kim-preshoff

Population statistics are like crystal balls -- when examined closely, they can help predict a country's future (and give important clues about the past). Kim Preshoff explains how using a visual tool called a population pyramid helps policymakers and social scientists make sense of the statistics, using three different countries' pyramids as examples.

Lesson by Kim Preshoff, animation by TED-Ed.