Infographic chart depicting the world's population by age group. The most numerous age group are the under 20's (2.6 billion people). The least numerous are the people aged over 100 (0.6 million). Europe has the oldest population followed by North America. Compared to population data from 1950, there are a smaller proportion of people below 20 years old in 2020. Data from the United Nations and Pew Research Centre.