The line graph compares the manufacture levels of petroleum , coal and natural gas in a European nation between 1981 and 2000.
It can be seen that there was upward trend in the production of petroleum and natural gas over the period except coal. In addition , the figure for petroleum consistently ranked in 1st place
At the beginning of the period , the amount of petroleum produced was nearly 100 million tonnes , while that of natural gas stood at 40 million tonnes. After that , it increased significantly to about 130million tonnes and did not change from 1983 to 1987. After declining sharply to roughly 92 million tonnes in 1991 , there was a sharp increase of about 28 million tonnes ( 120 million tonnes ) in the manufacture levels of petroleum in 2000 . Similarly , the figure for natural gas was stayed constant from 1981 to 1994, then it rose significantly to over 80 million tonnes in the end of the period .
By contrast , from 1981 to 1984 , there was no change in the amount of coal that a European country produced . Before dropping gradually to under 40 million tonnes in 2000 , there was a sharp decrease of about 30 million tonnes in 1985.