Oil Price Changes, Vacancies, and the Natural Rate. During the mid-1970s, changes in oil prices required products to be produced by different types of firms in different locations. This raised the...

Oil Price Changes, Vacancies, and the Natural Rate. During the mid-1970s, changes in oil prices required products to be produced by different types of firms in different locations. This raised the number of vacancies relative to the unemployment rate. According to the theory of William Dickens, how did this affect the natural rate of unemployment? (Related to Application 1 on page 359.)