With the chime of the NYSE closing bell at 4 p.m. on Friday, the markets locked in their third straight week of losses, with this week seeing the most severe declines. It was the worst week for the Dow Jones Industrial Average (DJINDICES:^DJI) since June; the index lost 2.1% of its value in just five days of trading, as markets sold off after President Obama's re-election Tuesday night. The Dow limped into the weekend trading sideways, up four points, or 0.03%, to close at 12,815.

The eye-popping underperformer in the index today was Walt Disney (NYSE:DIS), which shed nearly 6% of its market cap in the first day of trading after reporting quarterly results. Despite growing profits at a double-digit clip in the quarter, Disney's outlook made investors cringe; the company predicted rising costs would dint bottom line numbers in the coming year. If the company continues to spend as freely as it did with its recent $4 billion acquisition of Lucasfilms and the Star Wars franchise, it's not hard to see how costs could get out of hand quickly. 

Another big market mover on Friday was the car-sharing service ZipCar (NASDAQ:ZIP.DL2), which ended the day nearly 16% higher, after briefly trading up more than 25% in after-hours trading yesterday. The excitement stemmed from impressive quarterly results showing a customer base around 770,000 strong. On top of that, profits soared 560% and the company projected that 2012 would be its first full year of profitability. Not a bad news day, all in all.

The two top gainers in the Dow today were equipment manufacturer Caterpillar (NYSE:CAT), up 1.4%, and defense contractor and aerospace giant Boeing (NYSE:BA), which gained 3.1% for the day. Caterpillar stock generally rises and falls with positive and negative macroeconomic data --more so than most equities -- and its rise today was due to bullish consumer sentiment numbers, which came in at five-year highs. Boeing shares, while also buoyed by the macro data, were largely bid up because the company confirmed an order of 20 737s, bringing new orders on the year to over 1,000 units.

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