Colchero M Arantxa, Salgado Juan Carlos, Unar-Munguía Mishel, Molina Mariana, Ng Shuwen, Rivera-Dommarco Juan Angel
Center for Health Systems Research (CISS), Instituto Nacional de Salud Pública (INSP), Cuernavaca, Morelos, México.
Nutrition and Health Research Center (CINyS), Instituto Nacional de Salud Pública (INSP), Cuernavaca, Morelos, México.
PLoS One. 2015 Dec 14;10(12):e0144408. doi: 10.1371/journal.pone.0144408. eCollection 2015.
In 2014 an excise tax to non-alcoholic sweetened beverages (SSB) was implemented in Mexico. The objective of this paper is to study whether and to what degree these taxes passed-through onto SSB prices in urban areas overall and by region, type of beverage and package size. Prices were obtained from the National Institute of Statistics and Geography from 2011 to 2014. We applied a pre-post quasi-experimental approach using fixed effects models. In sensitivity analysis we applied other model specifications to test the robustness of the findings and we also present weighted estimations based on household purchases. The dependent variables are real prices of a specific beverage category; the main independent variables are dummies for each month of 2014, and the models adjust for time trends and seasonality. Results suggest that the SSB tax passed along to consumers for all SSBs and we found overshifting for the carbonated SSBs. A greater effect is seen among the small package sizes, and we see heterogeneous effects by region. Estimating the effect of the tax on prices is important to understand the potential effect on consumption.
2014年，墨西哥对非酒精甜味饮料（SSB）实施了消费税。本文的目的是研究这些税收是否以及在何种程度上转嫁到了城市地区总体以及按地区、饮料类型和包装尺寸划分的SSB价格上。价格数据来自国家统计和地理研究所2011年至2014年的数据。我们采用了使用固定效应模型的前后准实验方法。在敏感性分析中，我们应用了其他模型设定来检验研究结果的稳健性，并且我们还给出了基于家庭购买情况的加权估计。因变量是特定饮料类别的实际价格；主要自变量是2014年每个月的虚拟变量，并且模型对时间趋势和季节性进行了调整。结果表明，SSB税转嫁给了所有SSB的消费者，并且我们发现碳酸SSB存在过度转嫁。在小包装尺寸的饮料中可以看到更大的影响，并且我们发现不同地区存在异质性影响。估计税收对价格的影响对于理解其对消费的潜在影响很重要。
