most buyers are subsidized, although age-rating restrictions affect pre-subsidy premiums, participation is primarily driven … by subsidy generosity rather than pricing decisions. Combining pre and post-reform data on prices and enrollment we find … that age-rating restrictions altered pre-subsidy premiums: $230/year for under-50 buyers and -$900/year for over-50 buyers …

This paper shows how in Medicare Part D insurers' gaming of the subsidy paid to low-income enrollees distorts premiums … concentration index measuring the manipulability of the subsidy can explain a large share of the premium growth observed between …

how different subsidy schemes affect insurers' incentives. I combine data on household-level enrollment and plan … to assess equilibrium outcomes under alternative subsidy designs. I estimate that younger households are significantly …

7.6\%. Our second and third contributions are more novel. We use a sharp discontinuity in the subsidy rates and find the …