The pie charts illustrate which sources The United States of America used for energy in two decades.
Overall, oil was the main source of power, while hyrdroelectric power used slightly. Coal and nuclear power rose, however, others decreased.
In 1980, the majority of energy received from oil, and it was 42 percent. Although it decreased in 1990, it was still more than others. Furthermore, natural gas consisted 26 percent in 1980, and in next decade it dwindled just 1 percent. Despite oil and natural gas, coal rose in 1990, and was 27 percent which was 5 percent higher compared to 1980.
On the other hand, hydroelectric power was the only source that remained same in both years. Therefore, it consisted only 5 percent of the main energy sources in 1980 and 1990. However, nuclear power was the second less used source after hydroelectric power, its use increased 5 percent in 1990, and reached 10 percent.