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After World WarⅡ，the United States experienced rapid economic growth and enjoyed a long period of prosperity after a short period of post⁃war readjustment.By 1960，87％ of American families owned a television set and 75％ owned a car.About one⁃third of the population lived in suburbs as of 1960.

Many factors contributed to this long⁃term prosperity.The government’s postwar policy for demobilized soldiers also contributed to economic prosperity.In order to avoid what had happened after World WarⅠwhen large numbers of demobilized soldiers created a labor surplus and unemployment，Congress passed the Servicemen’s Readjustment Act in 1944.The Act，popularly been known as the GI Bill，provided millions of demobilized soldiers with free college education and loans to purchase farms，start businesses，or buy homes，as well as unemployment compensation.The GI bill created a well⁃educated labor force that contributed to the country’s prolonged economic growth.

In addition，pent⁃up demand for consumer goods that had been unavailable during the war stimulated production.Scientific research and development programs promoted by the government also played a major role in post⁃war prosperity.Congress established the National Science Foundation in 1950 to encourage scientific research.After the Soviet Union launched the world’s first man⁃made satellite，Sputnik，in 1957，the United States put even greater emphasis on education and research.Between 1957 and 1970，federal appropriations for research almost tripled.During the same period，federal funding for higher education quadrupled and college and university enrollment increased by 500％.This emphasis on education and research resulted in many technological breakthroughs which led to great increases in productivity.For example，the development of integrated circuits had revolutionary effects in many fields，including communications，medicine，and the computer industry.Another major result was achieved in 1969，when the United States successfully landed astronauts on the moon.

Finally，America’s post⁃war foreign policy also contributed to domestic economic growth.The program known as the Marshall Plan provided billions of dollars of aid to help European countries rebuild from the war，and the recipient countries then used much of the money to purchase goods from the United States.In the early 1950s，the Korean War also stimulated military production and spending.All of these factors contributed to the long⁃lasting economic boom after the war.

However，the run of economic prosperity ended in the 1970s.Inflation，started during the Vietnam War and worsened by the rise of oil prices，made the economy stagnant.The economy recovered during the 1980s and began to grow quickly in the 1990s，thanks in part to boom in the telecommunications and computer industries.

In the 1990s，the United States moved towards a post⁃industrial economy.Service and information⁃processing industries，rather than manufacturing，are the most important part of the economy today.American manufacturing companies，notably in the iron，steel，auto，and textile industries，moved much of their businesses overseas to take advantage of low⁃cost labor and gain easier access to global markets.Now，it is very difficult to find clothes or even manufactured products of any kind made in the United States in America’s big chain stores such as Wal⁃Mart，K⁃Mart，and Target.

The economic boom ended at the beginning of the 21st century and a new round of economic recession started.The unemployment rate was high and many businesses declared bankruptcy.The“Great Recession”caused by the financial crisis of 2007 lasted for several years until the economy began to slowly recover around 2011.However，the American economy as a whole is still by far the largest in the world.