Tuesday was a day of wild swings for the stock market, with triple-digit moves in both directions finally settling out to sizable gains for the major market benchmarks. Even as investors continued to hope for better economic conditions around the world to improve prospects for global companies, several stocks failed to follow the general trend of the market higher. Among them were Pep Boys (NYSE: PBY), Brink's (NYSE:BCO), and Safeway (NYSE: SWY), whose share prices fell dramatically today -- although with Safeway, there's a catch that investors need to be aware of before drawing the wrong conclusion.

Pep Boys plunged 15% after the auto merchandise and repair chain announced disappointing quarterly results this morning, including a surprise loss when investors had expected a modest profit. Same-store merchandise sales fell 3%, largely offsetting gains in service-related revenue and reflecting lower retail prices for tires. The bigger question for Pep Boys, though, is whether its hybrid parts-and-service model will prove to be more effective than the pure-play parts strategy that many of its rivals use. Given the age of cars on the road today, there's little doubt that many auto owners need Pep Boys and its peers, but whether they'll actually take advantage of parts and service retailers is another question entirely.

Security specialist Brink's dropped 11% after the company said that it would have to write down the value of its Venezuelan operations using the devalued exchange rate for the Venezuelan bolivar. U.S. investors might not be aware of the international nature of Brink's security services, but Brink's got almost 45% of its revenue last year from Latin America, almost doubling its North American revenue. Moreover, with Latin America giving Brink's more of its operating profits than any other, the hit from the Venezuelan asset writedown will be much more extensive than most investors in Brink's expect.

Safeway's share price fell by 10% today, but the drop merely reflected the grocery chain's spinoff of its Blackhawk Network Holdings shares, which was completely yesterday afternoon. Under the spinoff, Safeway shareholders received about 164 shares of Blackhawk for every 1,000 Safeway shares they held, worth roughly $4 per Safeway share and matching today's price drop in Safeway stock. Blackhawk's high-growth prepaid payment and product services businesses gave Safeway an interesting level of diversification, but the transaction will help Safeway focus more on maximizing the value of its grocery business as it works to complete its merger with Albertsons later this year.

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