Stocks rebounded from yesterday's steep sell-off on Wednesday, recovering nearly all of Tuesday's losses. Federal Reserve Chairwoman Janet Yellen waxed optimistic about the economy in front of Congress today, assuring lawmakers that interest rates would remain low into the near future. Eight in 10 sectors finished safely in the black by the market's closing bell, with consumer services and tech ending as the lone decliners. With 22 of its 30 components logging gains, the Dow Jones Industrial Average (DJINDICES:^DJI) took Yellen's soothing words to heart, jumping 117 points, or 0.7%, to end at 16,518. 

While there's nothing like a good macroeconomic report card from the schoolmaster of financial markets (a.k.a. the Federal Reserve), the three stocks under today's microscope were each driven by fresh quarterly results. Walt Disney (NYSE:DIS) shares, for instance, finished near the bottom of the Dow, shedding 0.9%, despite the fact that Wall Street initially cheered its numbers. The entertainment behemoth posted record profits in the first quarter, handily beating consensus estimates with earnings per share of $1.11 where the market expected EPS just under $1. CEO Bob Iger spoke this afternoon about American consumers, saying that there's "not much visibility, but not much fear," in terms of their current and future spending habits. 

For the average Zulily (NASDAQ: ZU) investor, today was rife with fear, as shares cratered a staggering 29.7% after a disappointing earnings report. Shares of the female-facing flash-sales retail site have been incredibly volatile since the day of its IPO last November, when Zulily's stock -- it went public at $22 a share -- surged 87% by day's end to finish above $37. Today's skid sent shares back below that mark, as investors worried that Zulily may be a victim of its own success. Revenue in the first quarter rocketed 87% higher, but the young company struggled to fill orders in a timely and cost-effective manner, and the business wasn't even able to break even. 

Source: Whole Foods website

While Zulily is still in the process of defining itself, the fear from Whole Foods Market (NASDAQ:WFM) investors is that the high-end organic grocer has already defined itself. Both sales and EPS numbers came in under expectations, which sent the stock plunging 18.8% on Wednesday. In what had typically been known as a notoriously low-margin, unexciting business, Whole Foods took the grocery game to a new level as it capitalized on and participated in an organic food revolution. The question is whether high margins are here to stay as competitors muscle their way into the market, undercutting Whole Foods' prices. While today's slump gives long-term investors a more attractive entry point, personally I find its stores far too pricey to frequent. With even old-fashioned grocers now highlighting their organic options, I don't see my portfolio craving Whole Foods anytime soon, either.

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