The pie charts compare how the proportion of energy manufactured from various resources in the nation has changed from 1985 to 2003. Overall, Oil remained the leading types of resources over the period despite a significant drop in 2003. Both coal, natural gas experienced a dramatic rise, though other renewable grew more moderately. In contrast, nuclear dropped sharply at the end of the period, while hydro remained unchanged.
Starting at 52%, oil became the dominant source by a wide margin. However, it then fell notably to just 39% by 2003. By contrast, while constituting a small portion at 8% and 13% in 1985, coal and natural gas surged to 22% and 23% at the end of the period, respectively.
Nuclear ranked at the second place with 22% at the beginning, whereas it lost ground by 2003 after declining to just 8%. There was an upward tendency in other renewable, though it was just at a marginal level with 1% in 1985 and 4% by 2003. Unlike other types of resources, hydro remained stable throughout the period with 4%.