The graph shows information about how much fuel was produced in a European country over nineteen years, between 1981 and 2000.
Overall, it can be seen that petroleum generally had the highest level of production, while the amount of natural gas remained stable over the first half period.
As regards petroleum, the figure started at around 100 tonnes in the first three years, which was the highest level of the three main fuels at this point. After that, it maintained the same level at 130 tonnes from 1983 to 1987, then sharply decreased, reaching around 90 tonnes in 1992. Following this, the figure fluctuated at near 130 tonnes then gradually dropped in the last four years. If we look at natural gas, it began at just under 40 tonnes in 1981, then stayed steady until 1991. Finally, the production of natural gas rose gradually, peaking at around 80 tonnes in 2000.
Turning to the figure of coal, the production remained unchanged at 80 tonnes from 1981 to 1984. After that, there was a rapid decline to approximately 50 tonnes, then rose sharply, reaching around 70 tonnes in 1987. Subsequently, the figure went down considerably until the end of the period.