This morning I saw on DIGG an interesting question, How Many People Have Ever Lived on Earth?. The quick answer? 106,456,367,669 have ever been born.

I have often thought about this question every time I pass by a cemetery. I realize that not every person is buried in the ground, but I wondered how it was that we haven't run out of space to bury people considering so many are born every hour (16,000/hr in 2006) and so many people have died in the last few hundred years.

So I checked the size of the Earth's land mass and I found that it is about 148.94 million sq km or 488.6 trillion sq ft. So now knowing that there were never more than 100 billion who died I can make the following calculation:

Assuming it takes about 7x2 or 14 sq ft to bury someone, if we actually buried every person who ever died it would take about 1.4 trillion sq ft of the Earth surface or less than 1/5^th of 1%. And since we don't bury every one, and sometimes we bury them on top of each other in mass graves a la Saddam Hussein, and sometimes we just pave over old graveyards and start over fresh elsewhere, it now made sense why cemeteries take up so little space.

Other trivia about our population:

The population of the world now stands at 6.5 billion souls [760 KB PDF]. Interestingly, almost 60% (3.862 billion) of that total live in only ten countries.

• China 1,311


• India 1,122


• USA 299


• Indonesia 225


• Brazil 187


• Pakistan 166


• Bangladesh 147


• Russia 142


• Nigeria 135


• Japan 128