<P> Regulation of the oil market has been a major player in oil history . Policies affect the market in a variety of ways such as; price, production, consumption, supply and demand . The Oil market has a history of booms and troughs, which caused producers to demand government intervention . Many times this government involvement only made the situation worse, and many of the regulations were quickly ruled illegal and removed . Before World War II, many of the problems within the oil market were related to changing prices . During the 1920s, oil prices were beginning to peak leading to fears of oil depletion . In response to these fears, during Coolidge's term, Congress enacted a depletion allowance to producers which led to a surge of investment in the oil business and the discovery of many new, large oil reservoirs . The next decade consisted of falling prices due to the new investment and overproduction . The declining prices led producers to demand some form of price support system . One example of how prices were propped up was a pro-rationing order made by the Texas Railroad Commission, which restricted oil production and increased price . This order was soon ruled illegal by federal district court in 1931 . The 1930s was the beginning of large federal intervention in the oil industry and began with the creation of the National Industrial Recovery Act, in 1933 . This act allowed for natural price competition, instead of agreements between the major producers . However, this act was ruled unconstitutional in 1934 . </P> <P> While the time before World War II was filled with issues regarding price, the post war era consisted of increasing oil imports partly due to the price support established during the 1920s and 1930s . The artificially high domestic prices led to a surge of imports from lower priced foreign producers . In 1955, a clause was added to the Reciprocal Trade Act Amendments which gave the president the power to limit imports of a specific commodity, if that particular commodity was harmful to the security of the nation . This clause allowed Eisenhower to enact oil import quotas in 1959 which ultimately caused international oil prices to decline . These import quotas restricted international oil companies from the US market, and led them to form OPEC . During the 1970s, Richard Nixon put in place many phrases of price controls . After many new regulations that altered the original price control system, President Carter eventually began removing these controls in 1979 . During the Carter administration, in response to an energy crisis and hostile Iranian and Soviet Union relations, President Jimmy Carter announced the Carter Doctrine which declared that any interference with U.S. interests in the Persian Gulf would be considered an attack on U.S. vital interests . Ronald Reagan later expanded this doctrine . Since the 1990s, the oil market has been free of most regulations . </P> <P> The United States of America (USA) is the world's second largest producer and consumer of electricity . It consumes about 20% of the world's supply of electricity . This section provides a summary of the consumption and generation of the USA Electric industry, based upon data mined from US DOE Energy Information Administration / Electric Power Annual 2015 files . Data was obtained from the most recent DOE Energy Information Agency (EIA) files . Consumption is detailed from the residential, commercial, industrial, and other user communities . Generation is detailed for the major fuel sources of coal, natural gas, nuclear, petroleum, hydro and the other renewables of wind, wood, other biomass, geothermal and solar . Changes to the electrical energy fuel mix and other trends are identified . Progress in wind and solar contributions to the energy mix are addressed . Expected changes in the generation environment during the next 5 years are discussed . </P> <P> Electricity consumption data in this section is based upon data mined from US DOE Energy Information Administration / Electric Power Annual 2015 files In 2015 the total US consumption of electric energy was 4,144.3 Terawatt hours (TWh) (or million MWh or billion kWh). This was essentially flat from 2014 . This is broken down as: </P>

What are the main forms of electrical generation used in the us
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