The pie graphs provide information about how much electricity was produced by fuel source in two countries, Australia and France, in two separate years, 1980 and 2000.
Overall, it can be seen that the total generation of electricity increased in both countries over the period shown, from 100 units to 170 units in Australia, and from 90 units to 180 units in France.
Looking at the Australian data sets in more detail it is clear that electricity production from coal increased from 50 units in 1980 to 130 units in 2000, which was the biggest change on the charts. Similarly, the amount of electricity which was generated from hydro power grew from 20 units to 36 units. The production of electricity from natural gas and oil both decreased, from 20 units and 10 units respectively in 1980 to 2 units in 2000.
Turning to the second set of pie charts, showing data from France, it is evident that electricity production from nuclear power increased the most, from 15 units in 1980 to 126 units in 2000. The generation of electricity from coal remained constant at 25 units in both years. The amount of electricity which was produced from oil increased slightly, from 20 units to 25 units over the period shown. Similarly, to Australia, the generation of electricity from natural gas decreased from 25 units in 1980 to 2 units in 2000.