Things look different when we take an international perspective. Last April, the United Nations published statistics on the world’s population as of 2010. As you can imagine, it’s a gargantuan head count (which relies on shaky numbers from governments in some countries), so estimates of the global population are broken down into five-year age groups.

Anyone between 25 and 29 is already older than most of the people in the world. That figure, too, has edged upward — but at a much slower rate. Between 1950 (the earliest year of data) and 1994, anyone in the 20-to-24 age group was older than the majority of the global population. Don’t feel glum though, Martha. As an American, you can expect to live to 79. That’s seven years longer than the average person on the planet.