According to the U.S. Census Bureau, the average life expectancy for everyone in the world is 66.26 years. Life expectancy varies somewhat by sex, with most men living 64.3 years and women living 68.35 years.
Average life expectancy depends greatly on geographical location. For example, people residing in Australia have an overall life expectancy of 81.2 years, while people living in the United States have an average lifespan of 78.2 years.
The country with the lowest expected life span is Swaziland, South Africa, where average life expectancy is just 39.6 years.
In order to increase one's life span, a person must eat healthy, get regular exercise, avoid smoking and get regular checkups.