Is the economic sky falling? Reports that U.S. car and truck sales declined 3.7% in May, the first significant drop in over 18 months, contributed to a heavy selloff earlier this week on fears that worried consumers were finally tightening their belts.

But on closer examination, the factors that contributed to May's low numbers might have less to do with consumer worries or economic weakness than with a unique confluence of events -- including some interesting strategic decisions by the automakers themselves.

A blip? Or a trend?
You don't need more than a glance at the results to see that May certainly wasn't a typical month for U.S. auto sales. There were several out-of-the-ordinary highlights, including:

  • All hail mighty … Hyundai? The Korean automaker and its Kia affiliate were the big winners from the ongoing shortages of Japanese vehicles, posting a huge 20.7% gain. That was enough to put them into fifth place in the U.S. for the month, ahead of Honda (NYSE: HMC) and nearly equal with Toyota (NYSE: TM).
  • Return of the Big Three? The pecking order for U.S. sales in May went like this: General Motors (NYSE: GM), Ford (NYSE: F), and Chrysler, which finished ahead of Toyota for the first time in ages. Chrysler joined Hyundai as the month's other big winner with a 10% gain thanks to surprisingly strong new products and a solid marketing effort.
  • Big drops for Japan's Big Two: The flip side of the above was that Toyota and Honda were down 33% and 23% respectively, huge drops that are largely attributable to the lingering effects of the March earthquake and tsunami.
  • Big gains for the high end: BMW, Audi, Porsche, and Tata Motors' (NYSE: TTM) Jaguar all saw double-digit sales gains in May. Clearly, consumers at the upper end of the market aren't stepping out of the marketplace just yet.

Obviously, the ongoing supply problems in Japan had a lot to do with May's unusual results, and probably just as obviously, we're likely to see the pecking order return to something more familiar once production at Toyota and Honda (and to a lesser extent, Nissan) is fully restored.

Japan wasn't the only unusual factor
There's more to this story, though. Not only were popular Japanese models in short supply in May, but transaction prices were up for everyone across the board. The average total transaction price rose 2.1% to the highest levels ever recorded in May, according to That, more than economic jitters, may have discouraged buyers.

But why were prices up? Partly for obvious reasons -- short supplies meant that dealers were less willing to negotiate -- and partly for a reason that won't surprise industry-watchers: Incentives were down. Incentives, those "cash back" or "zero percent financing" offers we hear about in TV ads, are programs funded by the automakers to keep vehicles moving during times when supplies are high, competition is stiff, or when it's time to clear out inventory of older models. 

But automakers dropped their incentives spending an average of 19% in May. That's the lowest level in over five years, and it was pretty consistent across the board -- Ford's spending was down 20%, GM's 17%, and Toyota's 27%. That has been a trend in recent months independent of the Japanese supply issues. As part of Ford CEO Alan Mulally's push to prioritize profits over sales totals, the company has been pushing to reduce incentives spending as part of its strategy to increase overall transaction prices. The lesson here hasn't been lost on new managers at GM and Chrysler, who appear to be following suit after decades of overspending.

And for shareholders …
Ford and GM stock both dropped sharply after May's sales results were posted earlier this week, but I think that was an overreaction. In both cases, a closer look at the numbers shows promising signs. For instance, while GM's overall sales were down 1%, retail sales (which typically boast much higher margins than fleet sales) were up 9%, and retail market share was up as well.

Ford managers, meanwhile, felt that they could have sold more small cars had they had the inventory available, and have taken steps to boost production during the next few months. But like GM, Ford saw an increase in retail sales (5%) while fleet sales were down by about 8%.

It's going to take a little longer for Toyota and Honda shareholders to see where things are at. While both companies are recovering from the tsunami more quickly than expected, we're still several months away from a full restoration of production. It's only at that point that we'll be able to see if the companies have truly lost ground in the U.S. -- or if the last few months have just been a blip.

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