That's because of the way the work requirement rules are written, according to Anuj (Ah-nooj) Gangopadhyaya (Gang-oh-pa-dye), lead researcher for the study by the Urban Institute. Exemptions include full-time students and primary caregivers of children, which tend to be younger people.
But the study has several limitations. The rules exempt full-time students, but the data could not distinguish between full-time and part-time students. The data also could not count pregnant women or the medically frail, who are also exempt.