Asymmetric Demand Response when Prices Increase and Decrease: The Case of Child Healthcare

This study tests whether demand responds symmetrically to price increases and decreases—a seemingly obvious proposition under conventional demand theory that has not been rigorously tested. Exploiting rapid expansion in municipal subsidies for child healthcare in a difference-in-differences framework, we find evidence against it: when coinsurance, our price measure, increases from 0% to 30%, the demand response is more than twice that to a price decrease from 30% to 0%, a result consistent with loss aversion. This result indicates that, while economists and policymakers pay little attention, the price change direction matters, and that welfare analysis should incorporate this direction.