The pie charts illustrate proportions of energy production sources for the USA in two years: 1980 and 1990.
Overall, the amount of energy generated from oil and natural gas decreased throughout the period, whereas coal and nuclear power experienced an opposite trend. Hydroelectric power remained unchanged as the least popular energy source in both years.
In 1980, oil accounted for 42% of the energy production in the USA, and this figure dropped to one third of the total a decade later. Similarly, natural gas comprised 26% of the total in 1980 but the percentage declined to a quarter in 1990.
On the other hand, 22% of the country’s energy was coming from coal in the former year before it rose to 27% in 1990. Both nuclear power and hydroelectric power made up 5% of the energy generation in 1980. Nuclear power, however, doubled to 10% in the latter year, while the quantity of energy derived from hydroelectric power stayed stable.
