Last month, Sterne, Agee & Leach lowered its average 2015 to 2016 international thermal-coal price forecast by $10 to $15 per ton in response to the mild weather, lower natural-gas prices and higher-than-expected coal stockpile build with utilities during the winter season. The strong production and exports out of Indonesia and Australia have led to the current glut in thermal-coal markets, and the financial firm projects the oversupply to persist through 2015 with supply outpacing demand growth.

Steel stocks, to which XME allocates almost 47% of its weight, have treated the ETF far better. The Market Vectors Steel ETF (NYSEArca: SLX) has surged more than 12% over the past month.

SPDR S&P Metals and Mining ETF