The pie charts illustrate the amount of electricity production by different sources of fuel in Germany and Denmark by the years 1978 and 1998.
Overall, the total electricity production increased over twenty years in both countries. The main source of electricity was coal in Denmark, while in Germany nuclear power took the largest proportion in 1998.
In Denmark, the total production rose from 60 units to 160 units. In 1978, coal contributed 53 units, which dramatically increased to 122 units by 1998. The amount of electricity produced by natural gas and hydropower was the same in 1978; that became more than twofold for hydropower and dramatically decreased from 15 to 2 units for natural gas.
In Germany, the 1998 production was two times higher than the amount produced in 1978. The figure shared by nuclear power was 11 units in 1978, which sharply increased to 111 units by 1998. The main sources of electricity in 1978 were coal and natural gas, which accounted for 22 units, which declined to 20 and 6 units, respectively, by the next year. The amount shared by oil remained the same at 20 units in both years and was decreased from 5 to 3 units that were obtained from hydropower.