The graphs illustrate 
distribution
 of Add an article
the distribution
main
 sources of Correct article usage
the main
power
 to produce electricity in the United States in 1980 and 1990.
Use synonyms
Overall
, it can be seen that the consumption of oil and natural gas decreased, Linking Words
while
 nuclear Linking Words
power
 and coal increased their popularity over time.
In 1980, oil was the most favoured source of energy Use synonyms
by 
making up 42% of total depletion and did not lose its position even after 10 years. Change preposition
apply
This
 trend was followed by coal, which outnumbered crude oil as the second most used source of Linking Words
power
 and accounted for more than Use synonyms
one quarter
 of Add a hyphen
one-quarter
whole
. Natural gas saw a slight Add an article
the whole
fell
 in popularity and made up 25% in 1990.
Regarding other types of fuels, the hydroelectric method of collecting Replace the word
fall
power
 Use synonyms
made
 up Add a missing verb
is made
the
 same 
percentage of 5 for Change preposition
of the
given
 two years. Correct article usage
a given
On the other hand
, the amount of energy produced by nuclear Linking Words
power
 witnessed an increase of 50%.Use synonyms