The purpose of this study is to evaluate formally the short term impacts of the tax policy applied to Sugar-Sweetened Beverages (SSBs) in Chile. The Impuesto Adicional a las Bebidas Analcohólicas (IABA, or "additional tax on soft drinks") in Chile was enacted in October 2014, affecting any non-alcoholic beverages to which colorants, flavourings or sweeteners have been added. For beverages above an added sugar concentration of at least 6.25 grams per 100ml (or equivalent proportion), the tax was increased from 13% to 18%, while for those below this threshold the tax was decreased to 10%, producing an 8% tax difference between these beverage groups. This impact evaluation analysis of the Chilean sugar-sweetened beverage (SSB) tax will estimate the impact of increasing the tax as well as decreasing the tax on soft drinks. The study will use household level grocery purchasing data for Chile. The purchasing records are available from October 2011 to September 2015 (three years before; and one year after the implementation of the tax in October 2014). The investigators will use a series of quasi-experimental approaches to evaluate the causal impact of the SSB tax policy on consumers' behaviour as well as on industry responses in the form of pricing and price promotion decisions.