The two pie charts give information about the percentage of electricity produced by variety of energy sources in Scotland for 20 years ago and last year.
Overall, the proportion of coal, hydro natural flow, gas and hydro pumped storage all showed a declining trend over the period but the amount of electricity generated from oil, nuclear and other renewables illustrated higher usage over the course of 20 years.
To begin, the percentage of coal dropped most significantly out of other sources that exhibited a falling trend, it was reduced from 41.4% to 32.7% within 20 years. Although hydro natutal flow, gas and hydro pumped storage experienced a similar trend, there was only a minor decrease during 20 years, its figure dropped by 0.8%, 0.6% and 0.9% respectively.
In constrast, the proportion of energy usage in oil, nuclear and other renewables grew over the period. Firstly, the usable energy produced by oil and other renewables grew almost two times within 20 years, followed by this, nuclear method experienced growth but only for a small margin, it rose by approximately 7%.