Complex sentence: It found that Peabody Energy the world's largest private coal mining company had lost 80% of it's share price over this time, this was attributed to Environmental Protection Agency regulations and competition from shale gas.
Split into simpler sentences: It found that Peabody Energy, the world's largest private coal mining company, had lost 80% of its share price over this time. This was attributed to Environmental Protection Agency regulations and competition from shale gas.