The given line graph illustrates the information of manufacturing levels of the main fuels in a European country during the period from 1981 to 2000.
Overall, it is evident that natural gas was at the lowest level and surged in 1997, coal sharply declined, whereas, petroleum dramatically fluctuated over the course and was the dominat part. The production of natural gas and petroleum as a whole increased, but manufacturing of coal decreased.
The amount of natural gas remained unchanged (approximately 40 tonnes); however, in 1997 this amount rapidly climbed and peaked in 2000 at the level of 82 tonnes. In 1997 a convergence of the two data series occurred at a single point: coal and natural gas at 50 tonnes. As it was mentioned before, the production of coal sharply plummeted in 1985 and reached 50 tonnes, following this it rose to 70 tonnes and gradually decreased to the end of the period.
The manufacturing of petroleum fluctuated: soared from 100 to 130 tonnes from 1981 to 1984, remained stable to 1987, plunged to 95 tonnes in 1998 and reached its nadir in 1992 (approximately 90 tonnes). During the period from 1992 to 2000 primarily grew.
