U.S. sales for BMW jumped by 46% last month, making the brand’s August performance one of the best in both the mainstream and luxury sectors, second to only ultra-low volume Jaguar, which posted an even more impressive increase of 67% for the month.  BMW’s large increase in year-over-year sales was made possible by a strong display from the brand’s volume-leading 3 and 5 Series models, which saw extremely lofty gains of 67 and 158 percent, respectively.

Now for the question on everyone’s minds… What caused such a large YoY increase for the brand, and even more importantly, what exactly caused the explosion in 3 and 5 Series sales?

To explain the monstrous gains recorded last month, we must first circle back around and revisit what BMW’s new sales looked like in August 2012.  During this period, brand sales actually declined by a staggering 19% versus what was recorded over the course of the same period just one year prior.  Most of the August 2012 decline can be chalked up to depressed 3 and 5 Series sales, which combined to account for only 7,810 units, a decrease of 40% compared to 2011’s figure of 13,069.

The bottom line is BMW didn’t knock it quite as far out of the park as one may be led to believe when simply glancing at last month’s large 46% boost in sales, but instead produced a rather “normal” August.

There are a couple reasons why sales were depressed for the brand last summer.  If you remember back to late 2011 BMW announced that they would be supplying a 4,000 unit fleet of vehicles for use at The London 2012 Summer Olympics comprised of primarily, you guessed it, 3 and 5 Series sedans.  This might not sound like a lot of cars, but it certainly hurt overall supply when vehicles normally earmarked for public sale were removed from the marketplace.  Another key component in the lackluster sales performance was the fact that BMW was still coming up to speed with production of their newly redesigned bread and butter 3 Series sedan.

Overall days’ supply for the brand dropped steadily over the first seven months of 2012, eventually bottoming out in July with a ridiculously low seven days’ worth of supply, although things did begin to improve over the course of August as BMW managed to stabilize their month-end days’ supply by closing out the month with a much healthier 40 days.  Unfortunately, the damage was already done and final August 2012 sales figures ultimately suffered. At face value, while the BMW’s August sales numbers were certainly respectable, at the end of the day, there is much more to the story than meets the eye.