Converging circumstances weigh down PPDs In the 19 years prior to 2020 and the COVID-19 pandemic, the monthly difference between Class III and Class IV prices had exceeded $5 per hundredweight (cwt.) on only six occasions. In 2020, that difference occurred six more times. For deeper perspective . . . that was just six times in 228 months prepandemic and six times in the first 12 pandemic months. “In two of those months, the spread was greater than $10, and in three more of those months, it was greater than $7 per cwt.,” Cornell’s Chris Wolf shared during the May 5 These wide differences in Class III and Class IV prices have framed the discussion surrounding negative Producer Price Differentials (PPDs) in 2020 and have contributed a great deal of fodder to the discussion of Federal Milk Marketing Order (FMMO) change.