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According to census.gov, the Census 2000 of the US for adolescent population is as follows:10 to 14 years of age: 20,528,072; 7.3% of the total population of the US.15 to 19 years of age: 20,219,890; 7.2% of the total population of the US.Therefore, the population of 10 to 19 years of age in the US is 40,747,962 which would be 14.5% of the total population of the US.
According to census.gov, the 2007 ACS population estimate of person 21 years of age or older in the US is 212,012,169which is 71.0% of the total population of the US.
Age.
As of 2020, the population of the United States over the age of 75 is approximately 22.2 million.
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Roughly 22% of the US population is under the age of 18, according to the latest census data.
Cuban and Puerto Rican populations in the US exceed the median age of the total population, with median ages of 40.2 and 39.5 years, respectively.
33 percent are under the age of eighteen.
According to census.gov, the 2007 population estimate of people 10-14 years of age in the US is 20,609,318 and 15-19 years of age is 21,469,780. So there are 42,080,098 people aged 10-19 in the US. That is 14.1% of the total population in the US.
According to the United States Census, They do not log particular age groups. However they said 13.7% is over the age 65. http://quickfacts.census.gov/qfd/states/00000.html
The age structure of a population can provide insight into future population growth. In the case of the US, an aging population with a large proportion of older individuals may indicate slower population growth or even a decline. On the other hand, Rwanda's young population with a high proportion of children suggests a potential for rapid population growth in the future.
According to the 2010 US Census, 13% of the US population is age 65 or older.