Completed because of a request from The Good Car Girl, the embedded spreadsheet you see here was meant to look at seasonal changes in the U.S. automotive marketplace. You, however, can look at it with whatever questions you may have and find answers. Monthly sales data (supplied by Automotive News Data Center) can be found for every month over the last ten years. Beyond that, The Good Car Guy has allowed Google Docs formulas to go to work on averages.
As you’ll see, January is never a good month for selling cars, but you guessed that already. Of greater importance to new car dealerships, May is the best month for selling vehicles. In fact, in three of the last ten years May was the top-selling month. Only in 2008 was January not the lowest volume month, but that January was worse than any of the previous 84 months on the chart. Clearly the middle months of the year are better times to sell cars, but December is moderately decent, despite the Christmas shopping at Apple stores and Target.