The USGC 3-2-1 crack spread (purple line in chart below) averaged $65/bbl in August, up from $62/bbl in July and more than two-and-a-half times the $25/bbl averaged a year earlier. Diesel cracks (orange line) led the rally, climbing from $33/bbl in February to $92/bbl in August. Gasoline cracks (blue line) rose from winter levels of $15-$18/bbl to $53/bbl in July before easing slightly to $52/bbl in August. Diesel cracks were up 226% year over year, while gasoline cracks increased 121%, leaving refining margins well above year-ago levels. The gap between diesel and gasoline cracks widened to approximately $41/bbl in August from $25/bbl in July. The August increase in the overall crack spread was therefore entirely driven by stronger diesel margins, as gasoline margins declined modestly from July.
