Other factors contributed to the decline in unionism generally and UMW specifically. The coal industry was not prepared economically to deal with such a drop in demand for coal. Demand for coal was very high during World War II, but decreased dramatically after the war, in part due to competition from other energy sources. In efforts to improve air quality, municipal governments started to ban the use of coal as household fuel. The end of wartime price controls introduced competition to produce cheaper coal, putting pressure on wages.