The concept of securitization is generally associated with the Copenhagen school of security studies, which is generally taken to include Ole WÃ¦ver, Barry Buzan, and a range of other, more loosely associated, researchers.
Average annual number of employed coal miners in the United States, 1890-2014. US employment in coal mining peaked in 1923, when there were 863,000 coal miners. Since then, mechanization has greatly improved productivity in coal mining, so that employment has declined at the same time coal production increased. The average number of coal mining employees declined to 65,400 in 2015.
Coal, income, and poverty. There are 54 coal mines in the U.S. that produced more than 4 million tons of coal in 2006; these 54 mines are located in 34 counties. The median 2005 poverty rate in these 34 counties was 15.5% - 17% higher than the U.S. average of 13.3%.