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In demographics, the world population is the total number of humans living on Earth. , it was estimated at 7.3 billion. The United Nations estimates it will increase to 11.2 billion in the year 2100.〔 The world population has experienced continuous growth since the end of the Great Famine and the Black Death in 1350, when it was near 370 million.〔Jean-Noël Biraben (1980), "An Essay Concerning Mankind's Evolution". ''Population'', Selected Papers. Vol. 4. pp. 1–13. Original paper in French: (b) Jean-Noël Biraben (1979)."Essai sur l'évolution du nombre des hommes". ''Population''. Vol. 34 (no. 1). pp. 13–25. 〕 The highest growth rates – global population increases above 1.8% per year – occurred briefly during the 1950s, and for longer during the 1960s and 1970s. The global growth rate peaked at 2.2% in 1963, and has declined to 1.1% . Total annual births were highest in the late 1980s at about 139 million, and are now expected to remain essentially constant at their 2011 level of 135 million, while deaths number 56 million per year, and are expected to increase to 80 million per year by 2040.〔(【引用サイトリンク】title=World Population estimates by the US Census Bureau )〕 World population reached 7 billion in October 2011 according to the United Nations Population Fund,〔〔 and in March 2012 according to the United States Census Bureau.〔(【引用サイトリンク】title=World Population Clock – Worldometers )〕 The 2012 UN projections show a continued increase in population in the near future with a steady decline in population growth rate; the global population is expected to reach between 8.3 and 10.9 billion by 2050. 2003 UN Population Division population projections for the year 2150 range between 3.2 and 24.8 billion. One of many independent mathematical models supports the lower estimate, while a 2014 estimate forecasts between 9.3 and 12.6 billion in 2100, and continued growth thereafter. Some analysts have questioned the sustainability of further world population growth, highlighting the growing pressures on the environment, global food supplies, and energy resources.〔 Some scholars have estimated the total number of humans who have ever lived, arriving at numbers ranging from 100 to 115 billion.〔〔 ==Population by region== Six of Earth's seven continents are permanently inhabited on a large scale. Asia is the most populous continent, with its 4.3 billion inhabitants accounting for 60% of the world population. The world's two most populated countries alone, China and India, together constitute about 37% of the world's population. Africa is the second most populated continent, with around 1 billion people, or 15% of the world's population. Europe's 733 million people make up 12% of the world's population as of 2012, while the Latin American and Caribbean regions are home to around 600 million (9%). Northern America, primarily consisting of the United States and Canada, has a population of around 352 million (5%), and Oceania, the least-populated region, has about 35 million inhabitants (0.5%). Though it is not permanently inhabited by any fixed population, Antarctica has a small, fluctuating international population, based mainly in polar science stations. This population tends to rise in the summer months and decrease significantly in winter, as visiting researchers return to their home countries.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「world population」の詳細全文を読む スポンサード リンク
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