As of this month, the world’s population is now 7.2 billion, according to the United Nations, which celebrates World Population Day today. According to U.N. data, half of the people around the globe (3.6 billion) live in just a half-dozen countries. China has the world’s largest population (1.4 billion), followed by India (1.3 billion). The next most-populous nations – the United States, Indonesia, Brazil and Pakistan – combined have less than 1 billion people.
The demographic future for the U.S. and the world looks very different than the recent past. Growth from 1950 to 2010 was rapid — the global population nearly tripled, and the U.S. population doubled. However, population growth in future decades is projected to be significantly slower and is expected to tilt strongly to the oldest age groups, both globally and in the U.S.
For example, the U.N. projects that during this century, the number of people living to at least age 100 will increase more than 100-fold, from 181,000 in the year 2000 to over 20 million in the year 2100.