The world population is the total number of living humans on Earth. As of today, it is estimated to number 7.086 billion by the United States Census Bureau (USCB).^[1] The USCB estimates that the world population exceeded 7 billion on March 12, 2012.^[2] According to a separate estimate by the United Nations Population Fund, it reached this milestone on October 31, 2011.^[3][4][5]

The world population has experienced continuous growth since the end of the Great Famine and the Black Death in 1350, when it stood at around 370 million.^[6] The highest rates of growth – global population increases above 1.8% per year – were seen briefly during the 1950s, and for a longer period during the 1960s and 1970s. The growth rate peaked at 2.2% in 1963, and had declined to 1.1% by 2011. Total annual births were highest in the late 1980s at about 138 million,^[7] and are now expected to remain essentially constant at their 2011 level of 134 million, while deaths number 56 million per year, and are expected to increase to 80 million per year by 2040.^[8]

Current projections show a continued increase in population in the near future (but a steady decline in the population growth rate), with the global population expected to reach between 7.5 and 10.5 billion by 2050.^[2][9][10] Various longer-term estimates predict further growth, stagnation, or even overall decline in the global population by 2150.^[11] Some analysts have questioned the sustainability of further world population growth, citing the growing pressures on the environment, global food supplies, and energy resources.^[12][13][14]

Source: World population – Wikipedia, the free encyclopedia