This graph shows the production levels of the main kind of fuels in the UK which are petroleum, coal and natural gas, in the time between 1981 and 2000.
In the first years the petroleum has the most production of fuels, it is about 90 energy units and the coal is 80 units, yet the natural gas has the lowest production of 40 energy units.
Through out the years the coal has drop to be about 40 energy units and then raise to 60 units and stay fix for some time, the petroleum has a increase to 140 and stay steady for number of years, although the natural gas has 40 units for many years then start to increase until it reaches 100 units in 2000.
The petroleum faced sudden increase start at 1987 and reached the lowest in 1990 yet it is start in raies again to reach 14 and stay steady to 2000, through this years coal start and continue to decrease until it reach the lowest at 2000 by less than 40 energy units.
In conclusion the graph shows that petroleum has the highest protection through the years and coal has the lowest production, the natural gas start as the lowest one but reach to high production through these years but still lower than the petroleum.