# How do you calculate world population?

I remember seeing a news report couple of years ago that earth’s billionth baby was born that day.

How is world population calculated so accurately?

It’s impossible to count each and every person on the planet. Also, in many countries health services are not so devloped to track each birth or maintain records of individuals or voters etc. By statistical methods we can have an approximate number but can never be sure which day billionth person was born.

• They calculate it from statistics, including the birth rate, death rate and census data.

Let me give you the most exact figure and accurate figure of world population at the time I’m answering the question :

( Second Later)

( Second Later)

( Second Later)

( Second Later)

and counting

You can see the time answered the question

The following clock shows the accurate population at current time : http://www.ibiblio.org/lunarbin/worldpop

• They definitely don’t track every person being born and dying, but they do have pretty good information on the birth and death rates in even the least developed countries. They simply add the births and subtract the deaths, and that’s how they get it. The news report was basically mistaken.

Source(s): http://www.census.gov/cgi-bin/ipc/pcwe

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