Deming does not believe in Peak Oil theories and has pointed out that "predictions of imminent oil shortages have been made throughout the twentieth century . . . all previous predictions have been false." He has criticized the Hubbert model of peak oil production as flawed because "Hubbert-type analyses . . . depend on an estimate of the total resource size . . . [but the history of resources assessments shows that in the last 50 years, estimates of oil reserves have risen as fast or faster than cumulative oil production."