The diagram below shows the production level of the important fuel types in the UK from 1981 to 2000.
In general, petroleum and natural gas rose, while coal was decreasing at the production level. Coal and petroleum have some fluctuations for some time.
Production of natural gas picked up from 35 to 45 gradually in 10 years, between 1981 and 1991. After that, it showed up rapidly to 65 in just 3 years, and then it slightly recovered until 2000, and its final production was 90. Starting from 90, petroleum rose slightly between 1981 and 1984, and then it stood at 140 for 4 years until 1988. After fluctuating between 1988 and 1996, it finally reached 135 in production.
The only decreased kind of fuel was coal. It fluctuated between 1981 and 1986, thereby reaching the level of 60, which is 20 units smaller than its start. After this fluctuation, it gradually reduced and in the year 2000 reached 30, which is very small compared to others.
