STOCKS TUMBLE, AMAZON GETS CRUSHED: Here's What You Need To Know

First, the scoreboard:

• Dow: 16,361.7 (-139.8, -0.8%)
• S&P 500: 1,863.5 (-15.0, -0.8%)
• Nasdaq: 4,075.5, (-72.7, -1.7%)

And now the top stories:

• Amazon.com was by far the worst-performing stock in the S&P 500, tumbling 9.8%. On Thursday afternoon, the company announced quarterly financial results that were largely in line with analysts' expectations. However, some investors maybe concerned about the amount of risk management is taking on by spending so aggressively. "In our view, Amazon's Q1 revenue acceleration will be well received by some investors," noted UBS's Eric Sheridan. "However, the company's Q2 margin guidance implies another leg of the investment cycle to maintain/promote revenue growth - fulfillment (capacity, last-mile initiatives), advertising (support for Fire TV, Prime, Kindle hardware), & content (exclusive licensing deals, original production)."
• A number of high-priced, momentum stocks slid with the Nasdaq sell-off. Netflix, Facebook, and Priceline.com were among the stocks deepest in the red.
• Geo-political worries continue to plague markets. "[A]ccording to our sources, today's sell-off is roughly 80% due to Ukraine-related worries; judging by the accompanying flight-to-safety rally in both the 10-year U.S. Treasury and in Gold," said Rich Barry of the NYSE MAC Desk. "The bottom-line: going into a weekend when there is risk of escalated geopolitical turmoil in Russia/Ukraine, traders have a tendency to play the risk-off trade - understandably."
• The University of Michigan's consumer confidence index jumped to 84.1 in April from 80.0 in March. This was better than the 83.0 level expected. It was also the highest level since July 2013. The consumer expectations index climbed to 74.7 from 70.0, but lags noticeably. "While near term expectations have improved substantially, longer term expectations for personal finances as well as the overall economy have not improved as much,"said survey director Richard Curtin via Reuters.
• "We do not believe that a slower-than-expected recovery in the expectations component will weigh on economic activity, however, and we expect that the index of current conditions will continue to move higher as housing and labor markets improve," said Barclays' Cooper Howes.
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