HONOLULU (HawaiiNewsNow) - The U.N. reports the world population is 7.6 billion. In two years there were enough births to replace all deaths, plus 200 million. The world population did not reach 1 billion until 1804. But it reached 2 billion in 1927 and 3 billion in 1959 and 4 billion in 1974 and 5 billion in 1987 and 6 billion in 1999. The world population has risen 50% since the late 1980s despite lower fertility rates in every region of the world. U.S. life expectancy has doubled in about 130 years. The average American retires at 62 - 100 years ago, the average American died at 51.
We have dozens of cities around the world with tens of millions of people. By contrast, ancient Rome was probably about the size of Honolulu today.