Last month, electric and hybrid vehicles had their lowest sales numbers in more than six years, reports. Edmunds says that shoppers are still very interested in all-electric and hybrid-electric vehicles because more consumers are researching green cars on their site, but it’s not translating into sales mainly due to a lack of inventory.

Overall sales of hybrids and all-electric vehicles were down 30 percent in June compared to the same month a year ago and down 17 percent from May 2011.

June 2011 sales of the Toyota Prius were down 61 percent compared to June 2010, which Edmunds says is “the worst single month for Prius sales since September, 2004.” A Toyota spokesman told Edmunds’ Auto Observer that Prius sales were affected by low inventory due to the March earthquake and tsunami in Japan, and that inventory was down 90 percent as of June 1 compared to last year.

The Honda Insight experienced a sales decline of 32 percent compared to last June, while the Honda Civic Hybrid was down 30 percent.

Nissan’s all-electric Leaf, on the other hand, had its best sales month ever in June, and was up 50 percent compared to May 2011. “Deliveries of the Nissan LEAF topped 1,700 units, our best ever month, as we focus on fulfilling the demand of an enthusiastic and growing group of consumers eager to make the switch to a 100-percent electric car,” Al Castignetti, vice president and general manager, Nissan Division, says in a statement.

“The industry can expect more of the same sales performance for electric and hybrid vehicles in July,” says Ivan Drury, industry analyst for Edmunds. “Inventory will still be a deterrent to sales, fuel costs are projected to keep falling and there are no new products to boost consumer awareness.”

If you’re shopping for a hybrid or electric vehicle, it’s wise to wait until inventories reach normal levels. You’ll not only have more options at the dealership, but you may avoid paying a premium due to vehicle shortages.

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