A newly released UN population study suggests that because the birth rates in wealthy countries is low and declining, the worker-retired ratio will not be able to support current social programs. "The report found that Japan would need 10 million immigrants every year for the next 50 years to maintain the current working-age to retirement-age ratio. Without migration, figures show it would be necessary to raise the retirement age to 77 to maintain the ratio." Sobering stuff. But just in case anyone is worried about the human race disappearing, check outWorldclocks.