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The diagram indicates the data from a 2008 report about the usage of the United States during the 50 years from 1980, measured in quadrillion units.

The number of petrol and oil start the year of 1980, remains stable in the first 15 years(about 35).then embrace with a sharp increase during the following years, which will reach 45 at 2030. Coal and natural gas have the similar trends in the first three decades (starts 15 and 20), both increasing stably to 21 at 2014. Professors predict that coal will surge to 25 at 2030, however, the natural gas remains stable (around 20). Nuclear and solar/wind start at 4 and experienced a slow climb. Hydropower restores itself in 2030 to the original level.