Share of Hybrid Electric Vehicle Sales are down

I was curious how Hybrid Electric Vehicles were doing, I had seen some data a few years ago showing the share of HEVs rocketing upward, to the point we could expect a large share of HEVs (or EVs) in the US fleet in a few years (perhaps a majority of new vehicles). However 2010 was a down year not only for sales (which given the overall economy is not surprising), but also share of sales (which given the drop in fuel prices from 2008, and perhaps the state of the economy, is not surprising, but perhaps troublesome). Sales are still dominated by the Toyota Prius. All technologies have their ups and downs, deployment is seldom perfectly smooth (though it looks quite smooth in retrospect).

Data are from US EIA and EPA Worksheets available. And Heavenrich (2010). Light-Duty Automotive Technology and Fuel Economy Trends: 1975 through 2010. Appendix D. U.S. EPA: Washington DC.