Adoption of electric vehicles, though it hasn’t taken off as fast as many in the industry thought it would, is nevertheless steadily increasing, and a major auto consumer group is tweaking its market watch approach accordingly.

AAA, the nonprofit motor club federation known for its roadside assistance, custom trip itineraries and auto insurance, has added public EV charging rates to its regular U.S. gas prices gauge. It says that the households of almost two million of its members have at least one electric vehicle. 

The organization rebranded its Gas Prices website to Fuel Prices to reflect the addition. The EV Charging Prices page of the site features a U.S. map with individual states color-coded according to their daily average public EV charging rates by kilowatt hour for all charging levels. It even shows a total number of public chargers in each state, from a low of 16 in Wyoming to a high of 11,342 in California.

The national average charging rate on Friday was about 35 cents per kilowatt hour.

One of AAA's early observations about EV charging rates versus gas prices is that the former tend to change little.

“One difference drivers may notice is that while gas prices bob and weave daily and require a chart to track, electric charging rates barely budge. Over the past six months, AAA has quietly monitored EV charging rates, and they have moved less than a penny,” said Spokesman Andrew Gross in a press release on the new charging rate offering. 

The new data will at least at first include just state and national figures, while AAA provides finer metro-area and county data for gas prices.

A chart allows fuel price watchers to sort by state, number of public chargers, and charging rate.

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