Sales of green cars and gas prices are inversely related.
As fuel gets cheaper, the financial incentive of a more-efficient car decreases, and consumers lose interest.
Given that trend, perhaps it's not too surprising that Ford will offer its dealers bonuses if they sell certain fuel-efficient vehicles to meet year-end sales targets.
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According to a memo obtained by The Detroit News, Ford is starting a pilot "Volume Growth Bonus Program" to encourage sales of the C-Max, Fiesta, Focus, Fusion, and Escape.
Together these models--all of which offer hybrid, plug-in, or downsized gasoline powertrain options--represent about 39 percent of the Ford brand's sales volume.
2014 Ford Focus
These dealer-bonus programs aren't uncommon in the car industry, but Ford's pilot program differs from others in that dealers will be able to make up monthly sales shortfalls to get the extra money.
So if a dealer doesn't sell enough of a certain model in November, it can make up the difference in December and still receive a bonus.
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The existence of these programs typically isn't made public, although dealers typically lower prices or offer other incentives on the models involved to meet set targets.
Dealer bonus programs are usually started to clear out inventory or counteract lagging sales--something most of the models involved here are experiencing.
Sales of the C-Max in October were down 22.5 percent last month compared to the same time last year.
2015 Ford C-Max Hybrid
Sales of the Fiesta were down 16.3 percent from this time last year, while sales of the Focus were down 9.1 percent.
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However, sales of the larger Fusion were actually 5.1 percent higher than they were in October 2013, while sales of the Escape were up 12 percent.
Note overall Ford sales are down 1.1 percent so far this year, but the percentage represented by the models tagged for the dealer-bonus program hasn't changed appreciably.