Given are pie charts comparing the major energy sources in United States in 2 years including 1980 and 1990.
In general, it is evident that oil was the most used source of energy in the USA. Additionally, while the figures for oil and natural gas declined, those for coal and nuclear power rose and the percentage of hydroelectric power used remained the same.
As can be seen from the charts, although the percentage of oil energy fell considerably from 42% to 33%, it remained the dominant energy source over the period. Natural gas accounted for roughly a quarter of the total energy supply in the United States during the whole period, with only a slight decrease of 1% in the last year.
The percentage of hydroelectric use remained steady at 5% over the time given. Coal made up 22% of the total energy in 1980, and this figure increased by 5% over the next ten years. The percentage of nuclear energy doubled to 10% in the end of the period.