The "Average Electricity Rate" is the average price (in cents) per kilowatt hour of electricity for end users across the four sectors designated by the U.S. Energy Information Administration (residential, commercial, industrial and transportation). The EIA defines electricity as a “form of energy characterized by the presence and motion of elementary charged particles generated by friction, induction, or chemical change.” An end user is defined as a “consumer that purchases electricity for its own use and not for resale.”
The prices reported here are from the February Electric Power Monthly that gives the December year-to-date figures for the prior year on its "Table 5.6.B. Average Price of Electricity to Ultimate Customers by End-Use Sector, by State, Year-to-Date through December 2019 and 2018 (Cents per Kilowatthour)."
Source: U.S. Energy Information Administration, Form EIA-826, Monthly Electric Sales and Revenue Report with State Distributions Report.