The pie charts show how the percentage of energy from five different sources in the USA changed in the years 1980 and 1990.
In general, the percentages of energy produced from coal and nuclear power increased slightly, whereas the proportion of energy from oil and natural gas decreased noticeably. Additionally, although there was a reduction in the figure for oil in energy production, it was used the most in both years.
Focusing on the largest energy sources first, the amount of energy from oil constituted 42% in 1980, the biggest energy source in the USA, which then decreased to 33% in 1990. As for natural gas, it produced 26% of the energy used in the country, before dropping to 25% after a decade.
On the other hand, coal was the third largest energy source. While it was used to generate 22% of the energy in 1980, the figure rose to 27% by the end of the period. Similar trend was observed in the figure for nuclear power, which increased from 5% to 10%. When it comes to the energy from hydroelectric power, its figure remained unchanged at 5% throughout the period.