Roberto CA, et al. - Researchers examined how beverage prices and volume of sales were influenced by the implementation of a beverage excise tax on sugar-sweetened and artificially sweetened beverages, which took effect in Philadelphia in 2017. According to findings, the beverage excise tax on sugar-sweetened and artificially sweetened beverages led to a significant rise in beverage prices and a significant decrease in volume sales of taxed beverages, although purchases in neighboring areas partially offset the changes in sales volume.

Methods

• Using a difference-in-differences approach, researchers analyzed sales data to compare changes between January 1, 2016, before the tax, and December 31, 2017, after the tax.
• They examined differences by store type, beverage sweetener status, and beverage size.
• Large chain store sales in Philadelphia, Baltimore, and the Pennsylvania zip codes bordering Philadelphia were included in the commercial retailer sales data.
• Nearly 25% of the ounces of taxed beverages sold in Philadelphia were reflected in these data.

Results

• Researchers analyzed a total of 291 stores (54 supermarkets, 20 mass merchandise stores, and 217 pharmacies).
• In Philadelphia, they noted an increase in the mean price per ounce of taxed beverages: from 5.43 cents in 2016 to 6.24 cents in 2017 at supermarkets; from 5.28 cents to 6.24 cents at mass merchandise stores; and from 6.60 cents to 8.28 cents at pharmacies.
• In Baltimore, there was an increase in the mean price per ounce: from 5.33 cents in 2016 to 5.50 cents in 2017 at supermarkets; from 6.34 cents to 6.52 cents at mass merchandise stores; and from 6.76 cents to 6.93 cents at pharmacies.
• The two cities, however, differed with respect to the mean per-ounce price by 0.65 cents at supermarkets, 0.87 cents at mass merchandise stores, and 1.56 cents at pharmacies.
• In Philadelphia, total volume sales of taxed beverages decreased by 1.3 billion ounces (from 2.475 billion to 1.214 billion) or by 51.0% following tax implementation.
• However, the Pennsylvania border zip codes showed an increase in volume sales by 308.2 million ounces (from 713.1 million to 1.021 billion), offsetting the decrease in Philadelphia's volume sales by 24.4%.
• Between before and after-tax periods in Philadelphia, beverage volume sales in ounces per 4-week period decreased from: 4.85 million to 1.99 million at supermarkets, 2.98 million to 1.72 million at mass merchandise stores, and 0.16 million to 0.13 million at pharmacies.
• The investigators noted a decrease in the beverage volume sales in ounces in Baltimore from: 2.83 million to 2.81 million at supermarkets, 1.05 million to 1.00 million at mass merchandise stores, and 0.14 million to 0.13 million at pharmacies.
• At supermarkets, this was a 58.7% reduction, at mass merchandise stores it was a 40.4% reduction, and in pharmacies, a 12.6% reduction.