Life Expectancy in the US
Life Expectancy in the US 1960-2005
Background information: Life expectancy is the number of years the average citizen is expected to live. These predictions were created by the US Census.

Life expectancies in the United States have gradually over time.

By 2020, the average American is expected to live for about years.

has gradually increased over time; expected to live for about 79 years

Explanation:

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for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.