This pie chart iliustrate the proportion of five types of energy in the USA in 1980 and 1990.
Overall, in both years the significan source of energy was oil, while hydroelectric power and nuclear power energy sources were the least amoun of energy in USA.
Aditionaly, in ten years these, production rose across all major energy sources with exception natural gas and oil.
For the first year coal accounted for 22% and then rising slightly by 5% to 27%. Whereas how natural gas was decreased. It made up 26% in 1980 and fell to 25% in 1990.
Other sources such us hydroelectric power production remainded the same whithout changes. But nuclear power increase by 5%, reaching 10%. On the other hand oil production accounted for 42% in 1980, but dropped to 33% in 1990.
