Amazon's stock drops below 8 1/2-month long uptrend line and 50-day moving average

Amazon.com Inc. bulls beware, because the 5.1% after-hours tumble in the stock, after the e-commerce giant missed earnings expectations, may have marked the end of an 8 1/2-month long uptrend. The stock had closed Thursday at $818.36, right at an uptrend line that started at the Feb. 9 closing low, and also connected the closing lows in mid-September and last week. The break of an uptrend line suggests a new downtrend may be starting. The stock was trading around $777 after the close, which would also put it below its 50-day moving average, which extended to $799.05. The last time the stock closed below the 50-day MA, which many chart watchers use to track the short-term trend, was March 21. The stock had run up 70% while above the uptrend line through Thursday, and 46% while it has been above its 50-day MA. In comparison, the S&P 500 has climbed 15% since Feb. 9.

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