The Changing Nature of Work

Published: 2020


We provide new evidence on the changing nature of work and its influence on individuals’ capacity to work by linking historical measures of occupational job demands with harmonized data on individual abilities from a unique survey conducted in the RAND American Life Panel in 2018. We start by examining how job demands have evolved over time between 2003 and 2018 for different dimensions of abilities (cognitive, physical, sensory and psychomotor), overall and by educational group. We then decompose job demand changes into within-occupation changes and changes in the economy’s distribution of occupations. Finally, we provide evidence on how individuals’ work capacities have evolved over time due to job demand changes.

Key Findings

    • The decline in physically demanding work and increase in cognitively demanding work is unevenly distributed across workers by education. While workers with a high school education or less face increasing job demands across all four dimensions — cognitive, physical, sensory and psychomotor — over the 2003 to 2018 period, college-educated workers face decreasing job demands for all dimensions except sensory requirements, which nevertheless increase less for more educated workers than for lower educated workers).
    • Second, we find that most of these changes over time are due to changes in occupational requirements within occupation rather than due to changes in the national economy’s composition of occupations. For example, the required proficiency level for written skills increased more than fourfold for construction laborers between 2003 and 2018, while construction workers’ share of jobs in the national economy increased from 0.89% to 1.44% over the same period.
    • Finally, when work capacity is defined as the fraction of jobs in the national economy that an individual possesses the functional abilities to perform, we find that differential changes in occupational requirements translate into differential changes in individuals’ work capacity by educational group. Specifically, we find that the fraction of jobs available to individuals based on their current abilities grew between 2003 and 2018 for those individuals with at least some college, and that this increase in the size of the potential job set increases with education. Notably, we find that work capacity did not grow, and potentially shrank, for workers with a high school degree or less.


Lopez Garcia, Italo, Nicole Maestas, and Kathleen J. Mullen. 2020. “The Changing Nature of Work.” Ann Arbor, MI. University of Michigan Retirement and Disability Research Center (MRDRC) Working Paper; MRDRC WP 2020-415.