The given line graph illustrates three different categories of fuel that is petroleum, natural gas, and coal production over a period of 19 years.
Overall, it is evident that the the manufactre of petroleum remains at first place within a mentioned period however coal and natural gas shows some level fluctuation in their level of production.
In 1981, the level of petroleum products was around 85 units and it gradually increases to 140 units till 1986. While, it falls dramatically and reached to 100 units in 1990. However, it surged after 1991 and increased significantly and reached just over 140 units in 1991 and falled to 140 in 2000.
Coal was at higher level than natural gas up to 1984 and marked at 80 units in 1981. However it falled just below to 40 units and somehow it peaked up to 1986 and showed constantly decline till 1984 and limits to just a quarter in 2000. Natural gas was in a steady level till 1990 and it rose significantly and it reached to approxmate 100 units in 2000.
