Friday was a terrible day for the stock market, with major benchmarks plunging on news that trade tensions between the U.S. and China will likely ratchet up another notch. The U.S. announced plans to add another $100 billion in tariffs on imports from China, responding to China's imposition of retaliatory tariffs following the initial U.S. move on steel and aluminum imports. Investors also reacted negatively to the fact that despite these macroeconomic and geopolitical issues, Fed Chair Jay Powell stayed the course with the central bank's plans to continue raising interest rates throughout 2018. Even though markets plunged, some stocks managed to post gains. SUPERVALU (NYSE:SVU), GOL Linhas Aereas Intelligentes (NYSE:GOL), and Pacira Pharmaceuticals (NASDAQ:PCRX) were among the best performers on the day. Here's why they did so well.

SUPERVALU looks to sell itself

Shares of SUPERVALU rose 9% after reports surfaced that the grocery store chain is seeking help from an advisor to consider strategic options that could include an outright sale of the company. SUPERVALU has been under pressure from some of its institutional investors to take action to enhance shareholder value, and with the company having sold off key assets in recent years, now seems to be a reasonable time to consider finding a buyer for its remaining store chains. Blackwells Capital has said that it thinks that separating the retail operations of SUPERVALU from its wholesale distribution division would be a smart move, and it's conceivable that the end result of the grocery chain operator's deliberations could be to split itself up further if it results in attracting a good offer from a potential buyer.

Outside view of Cub Foods location with empty parking lot.

SUPERVALU owns Cub Foods. Image source: SUPERVALU.

GOL flies higher

GOL stock gained altitude, finishing 13% higher in the wake of a favorable report on its business. The company issued an investor update that included predictions for substantial gains in operating margin and passenger unit revenue, along with reductions in non-fuel costs and financial leverage. The Brazilian airline also said that load factors in March were up from year-earlier levels, stemming largely from consolidation of available aircraft and seats to encourage greater utilization of existing capacity. As Latin America recovers from years of tepid performance, GOL stands to gain from greater levels of economic activity in the region.

Pacira has an up-and-down day

Finally, shares of Pacira Pharmaceuticals gained 13%. The biopharma stock jumped in midafternoon trading when the U.S. Food and Drug Administration briefly posted a link that was supposed to be related to Pacira's Exparel drug, which has been under consideration for an expanded label indication. Today was the nominal deadline for the FDA to look at the expansion for approval, so investors were paying close attention to see if they could get any early signs of whether Exparel would get good news. Later in the afternoon, the gains pulled back after the FDA removed the link from its website. At this point, it's not entirely clear whether the regulatory agency has made a final decision or not, but investors are hopeful that no news will eventually be good news for Pacira.

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