美国股市奇特的九月效应

Another possibility posed by researchers: tax-loss harvesting. A 1986 law forced most mutual funds to move the end of their tax years to October. So, many portfolio managers might be selling stocks with recent losses in September and October to take advantage of tax breaks, says Scott Gibson, a finance professor at the College of William and Mary who has studied the phenomenon.
研究人员提出的另一个猜想是：税收亏损收割(tax-loss harvesting)。根据1986年制定的一项法律，大多数共同基金的税收年度必须在10月份截止。威廉玛丽学院(College of William and Mary)的金融学教授斯科特・吉布森(Scott Gibson)对此现象也进行了研究，他表示，因为这个规定，很多投资组合基金经理可能会在九月和十月卖掉最近有浮动亏损的股票，以获得减免税的好处。

In 1990, when the rules took full effect, stocks with recent losses that were widely held by mutual funds lagged their benchmarks by almost 7 percentage points in October. Those same stocks beat their benchmarks by nearly 7 points in November, as the effect wore off, Prof. Gibson says.
吉布森教授指出，1990年，上述法规完全生效时，共同基金普遍持有的最近浮亏的股票在十月份跑输对应的基准指数近七个百分点。而到了十一月，税收效应消失后，同样一拨股票又跑赢基准指数近七个百分点。

Since then, the effect has become less pronounced, presumably as more mutual funds caught on.
此后，税收效应的影响变得不再那么明显，这或许是因为有更多共同基金参与了进来。

But Prof. Gibson says it is strong enough that investors looking to pick up shares on the cheap would be well-served to wait. Companies that have more than 5% of their shares held by funds and have seen recent losses are candidates for continued drops in September and October, he says.
但吉布森教授表示，税收效应的影响还是很大的，希望抄底的投资者应当耐心等待。他说，基金持股比例超过5%且近期有浮亏的上市公司，其股价最可能在九月和十月继续下跌。

That would disqualify computer-seller Dell, which has dropped 10.8% in the last three months and is about 32% owned by mutual funds.
电脑销售公司戴尔(Dell)似乎很符合这个标准，该股过去三个月下跌了10.8%，其共同基金的持股比例高达32%左右。

Other companies with poor recent performance and high fund ownership include Delta, Ford, Hewlett-Packard,Netflix, and Research In Motion.
其他近期股价走弱且基金持股比例较高的上市公司包括达美航空(Delta)、福特汽车(Ford)、惠普(Hewlett-Packard)、Netflix和Research In Motion等。

But with rational explanations hard to come by, investors should stop short of making big moves out of equities, Mr. Stovall says.
但斯托瓦尔指出，对于美股的九月厄运，由于很难找到合理的解释，投资者也不应大举做空股票。

'You're better off treating this information the way you would the pilot coming over the loudspeakers and saying 'Please fasten your safety belt,'' Mr. Stovall says. 'He's not saying 'Don the parachutes and assemble by the door.''
斯托瓦尔说，对于这个九月效应和分析人士的提醒，投资者最好就像在坐飞机时对待机长通过麦克风的喊话一样，“系好安全带”就行了，而不应将机长的喊话理解为“背上降落伞包，到机舱门口集合”。