We're not entirely sure what it has to do with Earth Day, to be honest, but here's an odd little statistic.

Turns out that buyers of green cars--whether they're hybrids or plug-in electric cars--are somewhat more likely to pay cash for their cars than are buyers of all vehicles on average.

DON'T MISS: Who Buys Plug-In Electric Cars, And Why? CA Report Explains It All For You

The news comes via an Earth Day release from Experian Automotive, which found that last year, 18 percent of green-car buyers paid cash--versus just 15.2 percent of buyers in the whole market.

Experian's senior director of automotive finance, Melissa Zabritski, suggests that one reason for this is that hybrid- and electric-car buyers may have better credit.

2014 Ford Fusion Hybrid

2014 Ford Fusion Hybrid

"A possible reason for this," she said, "could be that consumers buying ‘Green’ vehicles are in the highest credit tiers."

That may, in turn, "indicate they have more disposable income than those buying a gas vehicle.”

ALSO SEE: Green Car People: Who Buys Electric And Plug-In Vehicles?

Experian also notes that 83 percent of alternative-powered vehicle buyers fell within the prime credit category--against 71.5 percent of gasoline-vehicle buyers.

And their average credit score of a green buyer was 737, while it was 711 for traditional vehicles.

2014 Nissan Leaf, Bear Mountain, May 2014

2014 Nissan Leaf, Bear Mountain, May 2014

The company lists the top-selling hybrid cars in 2014 as the Toyota Prius, the Prius C, and the Ford Fusion Hybrid. Last year's top hybrid light trucks, it says, were the Lexus RX450h, the Subaru XV Crosstrek Hybrid, and the Toyota Highlander Hybrid.

As for plug-in electric cars, last year's top three were the Nissan Leaf, Chevrolet Volt, and Tesla Model S.

Sounding a theme noted by many analysts, Zabritski suggested that gradually rising average fuel economy across all categories of vehicle could pose sales challenges for green vehicles.

MORE: Once More: Low Gas Prices Don't Hurt Electric-Car Sales

Regrettably, like so many comments from both industry analysts and media reports, her comment conflates the different markets of hybrid cars--which rise and fall with gas prices--and plug-in electric cars, which thus far have been unaffected by gasoline-price variations.

To see the data displayed in one neat package, Experian created an infographic, "A breakdown of the alternative-power-vehicle market"

Finally, Experian said, the five states with the highest percentage of alternative-powered vehicle registrations last year were California, Hawaii, Oregon, Washington and Georgia.


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