In the case of Toyota, whose Prius rules the hybrid-sales roost, the number sold dropped 3.2 percent.
"Part of that was inventory shortages caused by the tsunami [in Japan] and the floods in Thailand," said Wade Hoyt, a Toyota spokesman. "And part of it was gas. When gas prices go up, hybrid sales go up. When they drop or stabilize, then sales go down."
Because of the continuing effect of the gas prices and up-front hybrid costs, industry analysts don't feel there will be a significant rebound in hybrid/electric sales this year. (The cost differential between a hybrid and its conventional cousin can range from a few thousand dollars on lower-end cars to almost $9,000 for the hybrid version of the BMW 535i.)
All of which raises the question: Why are the manufacturers fielding a plethora of new electrified vehicles? Why will the regional debuts at the Philadelphia show include a redesigned Ford Fusion that will be sold as a plug-in hybrid as well as a hybrid, a Ford C-MAX Energi plug-in hybrid, and a smaller Toyota hybrid called the Prius c?
First of all, few people in the auto industry expect gas prices not to keep going up. Global demand is increasing, and the supply of fossil fuel is finite. Though Hoyt's right when he says, "Gas prices are like a football - you don't know which way it is going to bounce," most experts feel they will trend upward. And when they do, hybrids and electrics will become more attractive.
In the meantime, automakers face a more immediate reason to develop and promote hybrids: They need them to meet the looming increases in government fuel-economy requirements.
They have to improve their Corporate Average Fuel Economy (CAFE) considerably, and electric power is the only way to get there. Incremental improvements in mileage obtained by conventional internal-combustion engines just aren't going to be enough, and hydrogen is still way off in the distance.
The need to get CAFE figures up explains the relatively recent entry of Volkswagen, BMW, and Mercedes-Benz in the hybrid/electric wars. The trio unveiled five new hybrids and three electric concept vehicles at the recent Detroit show.
Because of the regulations, and what he called "consumers' sensitivity to gas prices," Mark Fields, president of Ford's Americas Division, told reporters at the Detroit show he felt hybrids and electrics were going to play an important role.
"Hybrids remain the centerpiece of our plan to meet the regulations," Toyota's Hoyt said. "It's our core technology going forward."
And the hybrid market is expected eventually to expand. McKinsey & Co., an industry consulting firm, released a report in which it said hybrids could account for 20 percent of car sales in just eight years, with all-electrics chipping in an additional 5 percent.
Hybrids at the Philadelphia Auto Show
The hybrids making their regional debuts at the Philadelphia Auto Show:
2013 Ford Fusion. In addition to several gas- engine choices, this family sedan will also be available as a hybrid and plug-in hybrid, making it the first midsize sedan to offer all three power trains.
The new Fusion offers sophisticated electronics and safety systems, and pretty remarkable mileage numbers. Ford expects best-in-class economy from both hybrid models.
The gas and hybrid Fusions will be in the showrooms this fall, with the plug-in following at the end of the year.
2012 Toyota Prius c. When it comes to market in March, this subcompact hatchback, above, (the "c" stands for "city") will be the smallest Prius model - and the cheapest, with a base price of less than $19,000.
Aimed at younger, urban buyers, the c boasts the best city fuel economy of any vehicle without a plug: 53 m.p.g.
Ford C-MAX Energi The C-Max will be offered in two forms: the Hybrid and the Energi plug-in hybrid, right, at the show.
Set to go on sale in the second half of 2012, the C-MAX is a small, five-passenger minivan that Ford prefers to call a multiple-activity vehicle (MAV), perhaps to evade the minivan's soccer-mom image.
Built off the new Ford Focus compact platform, the C-Max is sold with a gas engine in Europe, but only in hybrid form here. Ford says it expects the Energi to give the Prius plug-in a run for its money.
Contact columnist Al Haas