Latest benchmark commodity price with the prior value + % change. Pass commodity for one, or omit for all. Commodities: wti, brent, natural-gas, gasoline, diesel, heating-oil, propane, copper, aluminum, corn, wheat, sugar — i.e. crude oil (WTI + Brent), natural gas, gasoline, diesel, heating oil, propane, gold, copper, aluminum, corn, wheat, sugar. Each result names the FRED series ID + unit ($/barrel, $/gallon, $/troy oz, $/metric ton...). Daily benchmarks report a daily date; global-price series are monthly. Source: EIA / LBMA / IMF via FRED (St. Louis Fed).