Since 2010, Cars.com has been analyzing the content and origin of vehicles sold at dealerships around the country to determine which ones are the most American. In order to make the American-Made Index, final assembly of a vehicle must take place in the U.S. and at least 75 percent of the parts and content in the model must come from suppliers in the U.S. or Canada.
Over the last six years, the number of models Cars.com proclaims as American-Made has steadily declined, going from 29 in 2010 to just seven this year.
"It's almost become a race to zero with fewer and fewer models meeting the threshold for us to include them on the American-Made list." said Olsen.
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After vehicles meet the first two criteria, Cars.com factors in the sales of the model to rank which vehicles are the most american-made.
This year, there's a change at the top of the list. The Toyota Camry, which is built in Georgetown, Kentucky has replaced the Ford F-Series, America's top selling vehicle, as the most American-Made vehicle this year.
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The F-Series content of domestic parts and materials dropped from 75 percent to 70 percent, which means it no longer qualifies for the Cars.com list.
While the ranking is an interesting reflection of how the auto industry has become more global, it raises the question whether car buyers base their decisions on whether one vehicle is more American-made than another?
"I think there is a fair chunk of Americans who do care about this," said Olsen. "But the majority of car buyers still care more about things like price, reliability and brand loyalty."
Questions? Comments? BehindTheWheel@cnbc.com.