Number of hybrid cars in use in the United States

Hybrid cars are becoming the VCR/DVD-combo players of the automotive world.

Just 2% of US auto sales last year were of cars with both electric motors and internal combustion engines, according to a report published this month by New York-based consulting firm AlixPartners. That’s down from a peak of 3.1% in 2013.

So what’s behind the drop in demand? Technology. Hydraulic fracturing (aka fracking), a drilling method that led to a boom in US oil - and natural-gas production, has driven down the cost of gasoline. Prices at the pump are currently just $2.40 a gallon, according to the US Energy Information Administration, a government statistics agency, a decline of nearly 35% since 2013. Cheap gas has also rekindled Americans’ love of trucks and SUVs.