​Historically, the production of many perishable​ foods, such as dairy​ products, was highly seasonal.​ Thus, as the supply of those products​ fluctuated, prices tended to fluctuate tremendouslylong dash—typically by 25 to 50 percent or morelong dash—over the course of the year. One impact of mechanical​ refrigeration, which was commercialized on a large scale in the last decade of the nineteenth​ century, was that suppliers could store perishables from one season to the next. Economists have estimated that as a result of refrigerated​ storage, wholesale prices rose by roughly 10 percent during peak supply​ periods, while they fell by almost the same amount during the off season.