As was noted last week, employment in Kentucky’s coalfields has been declining for decades—not just during President Obama’s administration. But there’s another way that statisticians and data wranglers have developed to evaluate the industry: productivity.

The Kentucky Energy and Environment Cabinet measures productivity by dividing the total coal labor hours by the total production. The resulting number is the tons of coal each Kentucky coal miner extracts per labor hour. This is a ratio; as it takes miners longer to extract each ton of coal, productivity falls.

After decades of rising productivity—both in Eastern and Western Kentucky’s coalfields—the numbers started falling around the year 2000. As has been the trend, Eastern Kentucky’s productivity fell much faster than the figures for the western part of the state.

So, at the peak in 1997, a coal miner in Eastern Kentucky could mine about 3.83 tons of coal an hour. Now, he can only mine 2.1 tons each hour.

Looking at only the last 14 years, productivity dropped for both Eastern Kentucky surface and underground mines.

So, what does this mean?

Well, even the experts don’t really know.

Michael Mellish, a coal economist with the Energy Information Administration, said the past decade’s decline in productivity isn’t a solely Kentucky phenomenon.

He said: “1980s, 1990s, productivity at coal mines was increasing at like 6 to 7 percent a year across all the basins. You hit 2000, and all of a sudden, productivity goes negative.”

Unlike stark numbers of coal production or employment, policy factors like environmental regulations have less of an effect on productivity. (There’s one exception to that: see below). A few factors that do affect productivity:

  • Technology. When new, advanced mining equipment is put into use, it increases the number of tons of coal a miner can produce each hour.
  • Coal reserves. When coal seams get smaller, miners have to work harder and longer to produce each ton of coal, and productivity suffers.
  • Workforce. Mellish says there’s not great data about this, but conceivably as more experienced miners retire and are replaced by greener miners, productivity could suffer. Or, conversely, the newer, younger miners could be stronger and more productive than the older ones.

There’s one way environmental regulations could affect productivity. President Obama’s Environmental Protection Agency announced in 2009 that it would be scrutinizing mountaintop removal permits, which led to delays and backlogs in permitting. Hypothetically, if a very productive surface mine wasn’t permitted, it could have a negative effect on overall productivity numbers.

Even so, productivity declines began 14 years ago. And like the graph from last week, this doesn’t really fit in the whole “War on Coal” rhetoric that Kentucky politicians in both parties like to repeat.

Note: The Kentucky EEC’s current productivity data only goes back to 2000, and measures tons/miner labor hour. Previous years of productivity were included in old editions of the cabinet’s “Coal Facts” publication. Current EEC employees weren’t able to verify how those older numbers (1977-2000) were calculated. Also, the “total Kentucky productivity” figures include all coal industry employees, including office and preparation plant workers, while the “underground” and “surface” data just includes miners.

Erica Peterson is WFPL's Assignment Editor.