Ethane shot past 36 cents per gallon (gal)—an 8.4% jump—last week at Mont Belvieu, Texas, to accompany a 23.91% widening of its margin to almost 18 cents/gal.

It is now up 74% for the year in price and 521% (yes, 521%) in margin. Not bad if you like that sort of thing.

The near-term outlook is promising. U.S. domestic consumption is on track to increase by 55% from 2014 to 2019, the U.S. Department of Energy (DOE) calculated in a June report. Almost all domestic output is dedicated as a feedstock for petrochemical plants that manufacture ethylene. A slew of new ethylene plant projects will increase U.S. capacity to nearly 600,000 bbl/d by year-end 2019.