Unseasonably warm weather during the winter in the U.S. curtailed demand for thermal coal by utility companies.

FORBES: Alpha Natural Worth $20 On Exports And Revival Of U.S. Demand

In Q4, gas prices rose by around 10% due to winter demand and rising demand from electric utility companies, which have been transitioning capacity away from coal towards natural gas.

FORBES: Kinder Morgan Preview: Trends Driving Its Results