If you look at the the chart there is a large jump in the data. "Notes on the data: Only birth dates after 1910 can be accommodated and only countries with populations of more than 100,000 people are included. Where available, the UN's medium variant and average figures from 2005-2010 have been used. World and country population clocks are estimates based on the latest UN figures and growth rates. They may not tally precisely with other clocks because of the way this application is configured."