World Population Counter
There is, of course, no totally accurate account of total world population. No one is continually recording every single birth and death. Nevertheless, it is possible to make estimates based on various census figures and rates of growth in various countries. The figure above is of net births minus deaths, and is based on estimates provided by the U.S. Census Bureau of a total population of 6,451,058,790 in mid-2005, currently increasing at a rate of 74,629,207 (1.15%) per year, or 2.37 people per second.
Although the total human population is steadily increasing, the rate of increase itself is slowing (the peak was in the 1960s). The overall slowing is a result of several factors—increased use of birth control, better education of women in developing countries, and rising standards of living. It is estimated that by 2050 the rate of increase will be about 0.46%—just over a third of current rates—by which time the total population will be over 9 billion. See Wikipedia for up-to-date information.
The total human population is a significant factor in the environmental crisis. Energy consumption, water use, food consumption, pollution, CO2 production, all increase as the population increases. This is compounded by the increasing affluence and material standards of living of the growing population, which raises the average per capita use of resources, particularly in developing countries such as India and China.