US hundredweight

The US hundredweight is a market unit before it is anything else. USDA price reports quote milk, cattle, hogs, rice and sugar in dollars per cwt, and the Class III milk future on the Chicago Mercantile Exchange settles in dollars per hundredweight, one contract covering 200,000 pounds, which is 2,000 cwt. A dairy farm's milk cheque, its cost of production and its break-even are all per-cwt figures, which makes the unit the denominator of the entire dairy economy.

The bridge to retail units is worth having. USDA converts milk at 8.6 pounds per gallon, so a hundredweight of milk is about 11.6 gallons, and a farm-gate price of $20 per cwt works out near $1.72 per gallon before hauling and processing take their share. On the beef side, fed cattle prices per cwt apply to live weight, so a 1,400 pound steer is 14 cwt of animal and its price moves in $14 steps for every dollar the market moves.

Trucking uses the same unit for a different job: less-than-truckload freight rates are quoted per hundredweight, and the freight cost allocation solver on this site works in exactly those terms, turning a rate per cwt and a chargeable weight into a landed cost per unit. The mass converters handle the rest, with the standing warning from the caution on this page: an unlabelled cwt in a British document is 112 pounds, not 100.