Measuring Consumer Responses to a Bottled Water Tax Policy
利用零售购买面板数据，采用双重差分法测量华盛顿州瓶装水税引入和取消对销售的影响，发现税收导致销量下降近6%，且取消后未完全恢复。
Abstract Using panel data of retail purchases, we measure the effects of the introduction, and later removal, of a bottled‐water tax in the state of Washington. We use a difference‐in‐differences approach to measure effects of the tax against untreated stores (in comparable control states) and untreated weeks (the pre‐period). We further estimate triple‐difference specifications comparing bottled water to juice and milk substitute products. Our results show that, when imposed, the tax causes bottled water sales to drop by nearly 6% in our preferred specification. Sales never fully recover, even after the tax removal. In terms of the heterogeneity of this effect, we find larger quantity drops in high tax rate areas and in the lowest and highest quintile income areas.