Global population doubles since 1974, hits 8 billion today

The world's population will cross 8 billion today, the UN estimates, doubling in 48 years from the time it hit the 4 billion mark in 1974.

Although the world population will continue to grow for the next few decades, this will largely come because of fewer deaths and an increase in life expectancy, shows UN population data. This also means that every billion adds to count of older people and hence pushes the global median age-the age that divides the population in two parts of equal numbers.

In 1974, the median age of the global population was 20.6 years, meaning half of the world was younger than 22.2 years while the other half was older than that age. World population hits 8 billion, but 'explosion' is over As birth rates keep falling, population will grow slower until it stalls and starts declining sometime this century.

We are at the 8-billion population mark now, and will cross 10 billion before the year 2100, but UN population projection data and many experts agree the world's population will not grow forever.