USGC refining margins lost momentum heading into December as product cracks pulled back from mid-November highs. Diesel — the key driver of strength earlier in the month — spiked to $47.34/bbl on November 18 but then slid to $32.34/bbl by December 1, as seasonal demand softened and supply concerns eased. Gasoline cracks followed a more modest arc, rising steadily through the first half of November before giving back gains and ending near $18.75/bbl by December 1. With both products weakening, the USGC 3-2-1 crack spread retreated from just over $31.56/bbl on November 18 to $23.25/bbl by December 1.
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