The world has reached a worrying demographic milestone. The US Census Bureau said the population of our planet surpassed 8 billion. The bureau estimated that the global population exceeded 8 billion in September. However, he said this was a rough guess. The moment could be a month or two earlier. The world population will continue to grow steadily. It has grown from 6 billion to 8 billion in the past two decades. The number of Earth's inhabitants doubled between 1960 and 2000. The rate of growth is slowing because of falling birth rates.

The Census Bureau put the slowdown in population growth to lower fertility rates. However, it said the population would be 10.2 billion in 2060. It said: "The world population is projected to keep growing.…We estimate the number of infants already peaked in 2017. Instead, population growth in the future will come from larger groups of people at adult ages." It added: "Population growth is the result of fertility, mortality and migration.…Nearly three quarters of the earth's population reside in countries where fertility is around or below the replacement level."