posted February 25, 2006 12:31 PM              

By Leonard David
LiveScience Senior Writer
posted: 24 February 2006
12:38 pm ET

A population milestone is about to be set on this jam-packed planet.

On Saturday, Feb. 25, at 7:16 p.m. Eastern Standard Time, the population here on this good Earth is projected to hit 6.5 billion people.

Along with this forecast, an analysis by the International Programs Center at the U.S. Census Bureau points to another factoid, Robert Bernstein of the Bureau's Public Information Center advised LiveScience. Mark this on your calendar: Some six years from now, on Oct. 18, 2012 at 4:36 p.m. Eastern Daylight Time, the Earth will be home to 7 billion folks.

These are estimates, of course, but clear trends emerge from the data behind them.

Population profile

A report issued by the Bureau in March 2004 noted that world population hit the 6-billion mark in June 1999. "This figure is over 3.5 times the size of the Earth's population at the beginning of the 20th century and roughly double its size in 1960," the study explained.

Even more striking is that the time required for the global population to grow from 5 billion to 6 billion—just a dozen years—was shorter than the interval between any of the previous billions.

On average, 4.4 people are born every second.

The population on Earth today is nearly four times the number in 1900 [graph]. Behind that phenomenal global increase is a vast gulf in birth and death rates among the world's countries. But according to population experts, this gulf is not a simple divide that perpetuates the status quo among the have and have-not nations.

Birth dearth

"What is worrisome about this demographic divide is not the differences among nations' population growth rates, but the disparities associated with these trends ... disparities in living standards, health, and economic prospects," explained Mary Kent, co-author along with Carl Haub, of a Population Reference Bureau report issued last month titled "Global Demographic Divide."

Kent, editor of the Population Bulletin, and Haub, a senior demographer at the Population Reference Bureau, reported that news of declining population in Europe fueled concern about a global "birth dearth," but there is continuing population growth in developing countries. The question, they asked, is which demographic trend is the world facing?

"The reality is that both trends are occurring," Haub said. "The dramatic fertility decline during the 20th century coincided with improved health, access to family planning, economic development, and urbanization."

Kent and Haub also reported that most countries will experience population growth through 2050, as the world adds a projected 3 billion more people to the total.