It's been a little more than three months since the Volkswagen diesel emission scandal erupted into the public eye.

Over that time, VW has revealed multiple violations of emissions rules across the globe for roughly 11 million of its TDI diesel cars sold not only by Volkswagen but also Audi and Porsche.

And details of its proposed fixed for 482,000 2.0-liter four-cylinder diesels and 85,000 3.0-liter V-6 diesels in the U.S. remain under assessment by the EPA and the California Air Resources Board.

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It's not every day that one of the world's three largest automakers admits to flouting the laws of another country, deliberately, over a period of many years.

So one of the most pressing questions in the global auto industry has been the impact of the scandal on sales of Volkswagen vehicles, in North America, its home market of Germany, and elsewhere.

The impact on September sales was mild, since the scandal broke during the last third of the month--and many sales during that period had been in process for a few days.

EDITOR'S NOTE: This article was first published on December 23. We have updated it with Volkswagen's U.S. and global sales figures for December and the full year.

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

For the month of November, VW Group sales globally were down 2.2 percent over November 2014. It delivered 833,700 vehicles worldwide, down from 852,900.

For 2015 as a whole, VW Group deliveries fell to 9.9 million from 10.1 million in 2014--a decline of 2 percent.

But that number includes sales increases in China and Europe that offset much steeper declines in North America, South America, and Russia.

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Declines in Russia and Brazil, however, were due to economic crises, not the diesel emissions scandal.

In the U.S., October sales for the Volkswagen brand were essentially flat over the same month last year.

That result was likely supported by a $2,000 "loyalty bonus" discount that was offered to current owners from October 7 through November 2.

2015 Volkswagen Passat TDI

2015 Volkswagen Passat TDI

After the bonus expired, total U.S. sales for the month of November fell 24.7 percent--roughly corresponding to the percentage represented by TDI diesels.

December sales for the VW brand fell 9.1 percent, and for the full year--a record-setter for the industry at 17.5 million vehicles--its U.S. sales were down 4.8 percent.

Every diesel vehicle sold by VW, Audi, and Porsche has been pulled off sale until regulators approve modifications to bring their emissions into compliance and those changes are implemented by dealers.

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In other markets, declines varied.

November sales of Volkswagen vehicles in the U.K. fell by 20 percent, and other VW Group brands--including Seat, Skoda, and Porsche--also logged lower sales.

The Society of Motor Manufacturers and Traders reported 12,958 Volkswagen registrations in the U.K. during November, against 16,196 in November 2014. 

Consumer Reports tests 2015 Volkswagen Jetta TDI diesel in 'cheat mode,' October 2015 [video frame]

Consumer Reports tests 2015 Volkswagen Jetta TDI diesel in 'cheat mode,' October 2015 [video frame]

Vehicle sales in the U.K. market were up 3.8 percent overall, meaning that Volkswagen's market share dropped from 9.4 percent a year ago to 7.2 percent last month.

And in Europe as a whole, according to an analysis last week by Reuters, Volkswagen lost market share as a small sales increase failed to keep pace with a surging market.

Data from the Brussels-based Association of European Carmakers showed an overall sales increase of 13.7 percent last month, with registrations rising to 1.12 million cars.

Sales of the Volkswagen brand rose just 3.1 percent, with VW Group sales as a whole gaining 3.9 percent--meaning market leader Volkswagen's share tumbled from 13.5 percent to 12. 2 percent.

2012 Volkswagen Passat TDI Six-Month Road Test

2012 Volkswagen Passat TDI Six-Month Road Test

But "while Volkswagen historically can rely on a large loyal customer base in [Europe], these ties are much less established in the US," according to Sebastiaan Van Doorn, an assistant professor of enterprise at Warwick Business School who has researched Volkswagen's management structure.

Van Doorn suggests that VW's market share declined, as was expected after the revelations of cheating, "but only marginally considering the extent of the scandal and the associated media coverage."


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