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What: Shareholders of Group 1 Automotive (NYSE: GPI) are getting a rude awakening this morning following the company's first-quarter results, which had the stock down as much as 11% earlier in the trading day.

So what: The actual results from this seller of various automotive products and parts weren't that bad. GAAP profit for the quarter came in $0.04 ahead of expectations at $0.66 on revenue of $1.4 billion. Where Group 1 fell flat on its face was with regards to its future orders, which are expected to see a major slowdown directly related to supply chain disruptions in Japan.

Now what: Group 1 relied on the sale of new and used vehicles for its greatest boost in revenue this quarter, so it's concerning that the company finds it "probable" that deliveries from Japan could be reduced by 30% to 50% this summer. The supply chain problem isn't contained to just Group 1. AutoNation (NYSE: AN) today lowered its sales forecast from 12.8 million vehicles to the mid-12 million range. We're beginning to see the effects of a slowdown in Toyota Motor's (NYSE: TM) output, and it's making auto retailers and parts suppliers seem increasingly less appealing. I'd advocate caution in this sector until after summer.

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