There is no trickle-down economy. It's all trickle-up. People with lowest wages, like agriculture and fast-food workers, do the hardest work, but most of the profit goes to those with higher wages – they can eat cheap food and think of new ways to better exploit the hardest working. Like scum, money accumulates at the top.
It's a well known fact that coal miners work really hard. There's a coal mine in rural Eastern Poanad, and I've met many people who worked there. The mine was started in 1970s. One of the guys told me how young people from local small farms flocked there – because the work was light. Eight hours, good pay, benefits. Piece of cake compared to 12 or 16 of extremely hard hours at their fathers' farms. The mine had machines, the small farms had horses. Poor horses.
@szescstopni
My grandfather was a coal miner in the pick-and-shovel, 1.3 metre seams days. 64 hour weeks.
I shared my flar temporarily with miners in the English 1970s miners' strike during demonstrations. Still hard work, but not the same.
Those miners were my height ~175 cm, compared with my grandfather, 142 cm.