We have talked about population growth before, but recent numbers show that the problem is far from over.

The worldâ€™s population surpassed 6.8 billion in early 2009, with no significant slowing in the pace of growth in recent years. Estimates by the United Nations Population Division indicate that humanity has been consistently gaining more than 79 million peopleâ€”a population almost the size of Germanyâ€™sâ€”each year since 1999.

Indicators including decreased assistance for family planning services, fertility levels well above replacement levels in many countries, and improvements in life expectancy for people living with HIV point to a human population that is growing somewhat more rapidly than demographers had expectedâ€”pointing to uncertainty in the commonly cited U.N. projection of 9.1 billion by 2050. One variable not taken into account in population projections is the impact of global climate change, which will likely most adversely affect people in developing countries.

According to the latest Vital Signs snapshot of population worldwide:

Â· More than 95 percent of population growth is occurring in developing countries, especially in Africa and Asia, regions that account for more than three-quarters of the current population. U.N. demographers estimate that by mid-century, Africa will be adding 21 million people a year to world population and Asia 5 million.

Â· Although the populations of Japan, Germany, Russia, and some Eastern European countries are already declining, U.N. demographers do not indicate a population peak among industrial countries as a group until 2036.

Â· Global spending on contraceptive supplies and services totaled just $338 million in 2007, considerably less than half the amount in 1995â€”despite a 20-percent increase in the number of people of reproductive age in developing countries.

This new population update includes the latest figures on annual additions to world population, donor family-planning expenditures, and the reproductive-age population in developing countries.

Read the Vital Signs analysis, â€œPopulation Growth Steady in Recent Years,â€ by Robert Engelman.