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The S&P 500 (SNPINDEX:^GSPC) climbed over the 1,750 mark for the first time in its history, continuing a long streak of record closes throughout 2013. But despite the broader market's gains, S&P 500 components Cameron International (UNKNOWN:CAM.DL), Symantec (NASDAQ:SYMC), and Akamai Technologies (NASDAQ:AKAM) all posted double-digit percentage losses on the week. Let's take a closer look at those companies to discover what sent their stocks plunging last week.

Cameron International took an 18% loss for the week, with most of that coming after the company reported third-quarter earnings that spooked shareholders. Cameron saw sizable revenue gains of 13%, but that was far less than the roughly 30% jump that investors had expected to see. A drop in net income of 15% was also disconcerting. On a positive note, Cameron saw a big jump in order backlog, showing that execution is more of an issue than a lack of demand. Nevertheless, if Cameron can't deliver on its promises, it won't keep those orders flowing in for long.

Security-software specialist Symantec also had to deal with earnings disappointment last week, suffering a 4% decline in revenue during its most recent quarter. What likely led to the stock's 13% drop on the week was Symantec's poor guidance for the full fiscal year. Symantec had expected solid growth in revenue and adjusted earnings per share, but the company now expects 1% to 1.5% declines in earnings per share on between 3% and 4% lower sales.

Akamai Technologies dropped 12% on fallout from its own earnings report, even though it featured solid growth in both earnings and revenue. Sales gains of 15% led to 32% higher adjusted net income, topping expectations. However, guidance was again the culprit, as revenue expectations left no room for growth above what investors had already expected. With news that the company is renegotiating pricing with a major media customer, shareholders fear that Akamai could see even bigger drops in expectations if those negotiations don't go well.