Population

As of mid-2006, the earth's human population stood at approximately 6.48 billion. In 1 c.e., it is estimated that the global population was between 250–300 million. Humans reached the first billion by about 1804; the second by 1927. The world population hit five billion around 1987, and six billion in 1999. This means that an estimated six percent of people ever born on earth were alive in 2002. The length of time it took to add an additional billion people to the planet shrank dramatically. Whereas it once took millennia to add a billion people, that number was added in just 12 years. The human population is expected to continue to grow for the next 70 years, peaking at 9.22 billion around 2075. At least ...