Source: US. Bureau of Labor Statistics
Release: Consumer Price Index
US. Bureau of Labor Statistics, Consumer Price Index for All Urban Consumers: Gasoline, unleaded midgrade in Midwest - Size Class D (under 50,000 persons) [CUUSD200SS47015], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/CUUSD200SS47015, August 24, 2016.