QQQQ: the NASDAQ-100 Index, launched in January 1985, is one of the most widely followed benchmarks in the world.

纳斯达克- 100指数，该指数于1985年1月开始投入使用的，是当今世界上使用范围最广的衡量标准之一。

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So if the QQQQ declines by 1%, then the UltraShort QQQ gains 2%.

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The Powershares QQQ Trust ( QQQQ) tracks the Nasdaq 100 index, which has been the strongest US market sector.

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Chart Analysis : The strongest market index since the summer lows has been the Nasdaq 100, as represented by the Powershares QQQ Trust ( QQQQ), but it has given up leadership over the past few weeks.

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