The line graph illustrates the figures for the production of electricity from various power supplies to service the city in New York from 1980 to 2000.
Overall, the total of petroleum is the largest source that is used for producing electricity. The amount of natural gas and coal share the opposite level in the whole period.
From 1980 to 1985, the amount of natural gas used for producing electricity underwent a stability at 100 kilowatt hours millions. Subsequently, it gradually and significantly increased to approximately 500 kilowatt hours millions in 1995. In the end of the period, the figures for natural gas used for producing electricity continued to grow to over 500 kilowatt hours millions.The amount of coal used for manufacturing electricity witnessed a minimal growth from over 200 to over 300 kilowatt hours millions from 1980 to 1985.Then, this is witnessing a gradual fall from over 300 kilowatt hours millions to under 200 kilowatt millions in the figures for coal and it remained stable just under 200 until the end of the period. In 1990, the opposite trend of the figures for coal and natural gas happened.
Between 1980 and 1985, the amount of petroleum used for manufacturing electricity increased enormously from under 400 kilowatt hours millions to 600 kilowatt hours millions. Subsequently, it declined to under 400 kilowatt hours millions in 1990. Finally, it increased again to over 700 killowatt hours millions in the end of the period. It is clear that the number of petroleum underwent a fluctuation.