Association between Tax Structures and Price Variability-Evidence from a Large Number of Countries

Background: Studies have shown that a specific uniform tax structure is the most effective tax structure for reducing price variability, and thus reducing tobacco consumption and prevalence. This conclusion, however, is based on a comparison of only a limited number of countries.

Objective:  To analyze the association between tax structures and price variability using data from many countries in order to provide evidence that can be generalized worldwide.

Methods: Cigarette prices from 75 countries during 2008-2011 were obtained from the Economist Intelligence Unit (EIU) and linked to the WHO tax structure measures, which are the percent of specific component among excise taxes and a dichotomous indicator of whether tiered rates exist. Price variability was measured using the ratio of the price difference between high- and low- priced brands to the price of mid-priced brands. Generalized Estimating Equations were used to estimate the association between tax structure and price variability while adjusting for a linear year trend.  

Findings: Consistent with the existing literature, preliminary results show that a tiered structure is significantly associated with higher price variability (p≤0.1). In addition, a higher percent of specific component among excise taxes is negatively associated with price variability, but this association is non-significant. This is likely due to the limited time dimension in the data.