The Chicago Board Options Exchange’s Volatility index, called the VIX (CBSX:VIX), is up about 16% this week, a signal that traders expect increased volatility.

While that’s arguably the case this week, it’s also worth noting that the index is bouncing back from rare lows last week. While unrest in Greece and Spain and a pullback in the U.S. markets have doubtless contributed to the VIX’s rise, this week’s climb is also due to last week’s drop.

On Sept. 19, the VIX closed at 13.88, under 14 for just the third time in the past five years. On Sept. 21, it closed at 13.98. But as of Wednesday afternoon, it was just above 16 — a big move in percentage terms but well below its long-term average of 20.5, said Randy Frederick, director of trading and derivatives at Charles Schwab.

A widely-watched measure of volatility, the VIX is derived from prices for options linked to the Standard & Poor’s 500 index (^GSPC); it typically drops as stock prices rise and vice versa.

It also has a reputation for bouncing around a lot.

“I like to say the VIX is like a pendulum — it tends to swing too far in either direction,” said Frederick. “It was at an incredibly low level a week ago, and when it gets that low it has a tendency to snap back.”

Frederick noted that the latest move is similar to August’s trend, when the index rose in the final week after dipping below 14 mid-month.

After closing at 13.45 on Aug. 17 — its lowest close since June 2007 — the VIX steadily rose and closed at 17.98 on Sept. 4 before falling again to its mid-month low.

Last week’s low was prompted by stocks’ strong performance in September on the back of the Federal Reserve’s announced third round of quantitative easing, as well as hopeful noises from the European Central Bank. Some even pointed to the feel-good effect of Apple Inc.’s (AAPL) iPhone 5 launch as boosting the market.

The market mostly held last week, with stocks closing down less than 1%. But protests southern Europe and some profit-taking by traders after a strong summer have seen a bigger dip this week, with the S&P 500 down 1.6%, the Nasdaq Composite index (^IXIC) off 2.6% and the Dow Jones Industrial Average (^DJI) down about 1%. Read about Wednesday’s drop for U.S. stocks.

It remains to be seen whether the VIX will repeat its recent cycle and fall again in October, though with Nov. 6’s presidential election, and increasing chatter about the so-called fiscal cliff, there could be some increased volatility in the fourth quarter, noted Frederick.

　　截至收盘，道琼斯工业平均指数下跌44.04点，收报13,413.51点，跌幅为0.33%；纳斯达克综合指数下跌24.03点，收报3,093.70点，跌幅为0.77%；标准普尔500指数下跌8.27点，收报1,433.32点，跌幅为0.57%。

　　嘉信理财交易与衍生品部门总监兰迪-弗雷德里克(Randy Frederick)表示：“我们看到市场为欧洲发生的事情感到紧张。我们都在电视上看到那里发生的骚乱。”

　　弗雷德里克表示：“任何时候股市大幅上涨了，希望落袋为安的人总是会寻找获利回吐的机会。”他指出，第三季度将在本周五结束，而标普500指数在9月份已经上涨了2.1%，在第三季度已经上涨了5.4%。

　　经济数据方面，美国商务部宣布美国8月新屋销量为37.3万幢，低于预期。据彭博社调查，经济学家此前的平均预期为38.0万幢。7月新屋销量为37.2万幢。房屋售价中间值从23.1万美元攀升至25.69万美元。

　　周二公布的房价指数连续第四个月上涨，并创下近两年来新高。

　　投资者们迎来了有关的西班牙的负面消息，昨日该国首都马德里发生针对紧缩的暴力抗议活动。在西班牙政府处境危急之时，该国最重要的经济地区加泰罗尼亚地区也突然宣布举行选举，可能为该地区宣布独立铺平道路。

　　西班牙政府预计将于周四公布2013年预算和经济改革方案，投资者仍在揣度该国是否以及何时会宣布申请救助。西班牙国债收益率周三大幅上涨，10年期国债收益率上涨27个基点，逼近6%。

　　希腊消息也令市场承压，欧洲央行执委会成员佐尔格-阿斯穆森(Joerg Asmussen)周三接受一家报纸采访时称，该行无法满足希腊的外部融资需求，只有欧元区成员国才能做到。据报道，希腊警方周三用催泪弹回击了投掷燃烧弹的抗议人群。

　　纽约商业交易所11月份交割的原油期货价格下跌1.39美元，收报每桶89.98美元，跌幅为1.5%，创下自8月初以来新低。12月份交割的黄金期货价格下跌12.80美元，收报每盎司1753.60美元，跌幅为0.7%。

　　周二，受美联储非投票成员查尔斯-普罗索(Charles Plosser)有关宽松货币政策无助美国经济增长的讲话打击，周二美股收跌。许多分析师同时警告称美国股市已经超买。周二道指下跌0.87%，纳指下跌1.4%。

　　周二美股下跌的部分原因是中国股市创2009年以来新低，而泛欧道琼斯斯托克600指数下跌1%以上，其中西班牙IBEX 35指数下滑3%。 (明煜)