World Populations

Most of the information here has been sourced by the United States Census Bureau. While looking through here keep in mind that according to a variety of other sources many of these projected population figures are vary conservative. These estimates are not considering expected advances in critical technological fields, for instance agricultural technologies, GMOs, and medical techs. All of these areas of continual exponential growth will have huge impacts on world population.
So based on the previous fifty years of population growth, there have been estimates put forward on what the next fifty years will bring. These estimates are very linear but are none the less interesting to look at.

This posting has been updated with recently obtained, up to date figures.

The world population (in 1900) - 1.633 Billion
(- U.S. Census Bureau)

The world population (April 2 2010) - 6.812 Billion
(- U.S. Census Bureau)

The world population reached the - 7.0 Billion mark on March 12 2012.
(- U.S. Census Bureau)
or October 31, 2011 - according to the UN Population Fund.

Project world population by 2050 - 9,202,458,484
(- U.S. Census Bureau)
(- United Nations Estimate) - 9,309,051,539

Population of people over 60 yrs old in 2050 - Over 1 Billion
(- United Nations)

2010 China population - 1,330,141,295
(- U.S. Census Bureau)

6/2012 (Estimate) China population - 1,343,240,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected China population 2020 - 1,384,545,220
(- U.S. Census Bureau)

Projected China population by 2050 - 1,303,723,332
(- U.S. Census Bureau)

In 1900 population of China or "Qing Dynasty" was estimated at - 300,000,000
(- Populstat.com)

2010 India population - 1,173,108,018
(- U.S. Census Bureau)

6/2012 (Estimate) India population - 1,205,074,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected India population 2020 - 1,326,093,247
(- U.S. Census Bureau)

Projected India population by 2050 - 1,656,553,632
(- U.S. Census Bureau)

In 1900 population of India (UK controlled) was estimated around - 200,000,000
(- United Nations)

2010 United States population - 308,984,298
(- U.S. Census Bureau)

4/10/2012 United States population - 313,339,815 - Estimate based on statistics.
(- U.S. Census Bureau)

Projected US population 2020 - 341,386,665
(- U.S. Census Bureau)

Projected US population by 2050 - 439,010,253
(- U.S. Census Bureau)

In 1900 population of the US was - 76,212,168
(- U.S. Census Bureau)

2010 Brazilian population - 201,103,330
(- U.S. Census Bureau)

6/2012 (Estimate) Brazilian population - 205,717,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected population of Brazil 2020 - 222,607,506
(- U.S. Census Bureau)

Projected population of Brazil by 2050 - 260,692,493
(- U.S. Census Bureau)

2010 Russian population - 139,390,205
(- U.S. Census Bureau)

6/2012 (Estimate) Russian population - 138,082,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected Russian population by 2020 - 132,242,117
(- U.S. Census Bureau)

Projected Russian population by 2050 - 109,187,353
(- U.S. Census Bureau)

2010 population of Japan - 126,804,433
(- U.S. Census Bureau)

6/2012 (Estimate) Japanese population - 127,368,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected population of Japan by 2020 - 121,633,376
(- U.S. Census Bureau)

Projected population of Japan by 2050 - 93,673,826
(- U.S. Census Bureau)

In 1900 the population of Japan is estimated to have been around - 42,000,000
(- wikipedia)

2010 population of The Philippines - 99,900,177
(- U.S. Census Bureau)

Projected population of The Philippines by 2020 - 119,328,726
(- U.S. Census Bureau)

Projected population of The Philippines by 2050 - 171,964,187
(- U.S. Census Bureau)

2010 population of United Kingdom - 61,284,806
(- U.S. Census Bureau)

6/2012 (Estimate) UK population - 63,047,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected population of United Kingdom by 2020 - 63,068,016
(- U.S. Census Bureau)

Projected population of United Kingdom by 2050 - 63,977,435
(- U.S. Census Bureau)

In 1900 the population is estimated to have been around - 38,000,000
(- Wikipedia)

2010 population of Spain - 40,548,753
(- U.S. Census Bureau)

6/2012 (Estimate) population of Spain - 47,043,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected population of Spain by 2020 - 40,119,891
(- U.S. Census Bureau)

Projected population of Spain by 2050 - 35,564,293
(- U.S. Census Bureau)

2010 population of Laos - 6,993,767
(- U.S. Census Bureau)

Projected population of Laos by 2020 - 8,642,456
(- U.S. Census Bureau)

Projected population of Laos by 2050 - 13,201,562
(- U.S. Census Bureau)

2010 population of South Africa - 49,109,107
(- U.S. Census Bureau)

6/2012 (Estimate) population of South Africa - 48,810,000 -Estimated in thousands.
(- U.S. Census Bureau)

Projected population of South Africa by 2020 - 48,529,675
(- U.S. Census Bureau)

Projected population of South Africa by 2050 - 49,400,628
(- U.S. Census Bureau)