This is the VOA Special English Health Report.

The United Nations estimates that the world reached seven billion people on Monday. No one can be sure. The United States Census Bureau does not expect that to happen until March.

Populations are growing faster than economies in many poor countries in Africa and some in Asia. At the same time, low fertility rates in Japan and many European nations have raised concerns about labor shortages.

Population experts at the United Nations estimated that the world reached six billion in October nineteen ninety-nine. They predict nine billion by twenty-fifty and ten billion by the end of the century.

China's population of one and a third billion is currently the world's largest. India is second at 1.2 billion. But India is expected to pass China and reach one and a half billion people around twenty twenty-five. India will also have one of the world's youngest populations.