One of the questions I get asked these days is whether a win by Mitt Romney or by Barack Obama would be better for the stock market. To which the only honest answer is "I have no earthly idea." Any competent and dispassionate market analyst will tell you that the financial and psychological states of the U.S. and world economies are the major factors, and that the President's influence on these matters is far less than most people think it is.

    Case in point: George W. Bush. He was a Republican, a free-market guy, right? Stocks, according to the conventional wisdom, should have boomed during his reign. After all, he dropped taxes on investment income to their lowest point in modern history in the name of helping investors and the economy. Well … oops! Rather than being a golden age for stock investors, his tenure was a disaster. The U.S. market lost 25.1% during his two terms, according to statistics assembled for me by Wilshire Associates. Had historical averages held, the market's total return -- capital gains plus reinvested dividends -- would have more than doubled investors' money during the eight years that Bush was in office.

    Instead, investors ended up with a quarter less than they started with.

    And guess what? The best first-term presidential market (at least so far) has come during the administration of … Barack Obama, who has been reviled on Wall Street for allegedly crippling corporate America with insults and regulation, and who has pushed through higher taxes on investment income of upper-echelon households. Yet stocks produced a whopping 95.9% total return from Obama's Inauguration through Fortune's mid-September presstime.

    当我请Wilshire计算每届总统任期的股市回报率时，我根本没有料到奥巴马会排在第一。我们的统计始于罗纳德•里根，是因为Wilshire是从1980年推出Wilshire 5000指数起开始跟踪每日的市场回报率。因此，1981年就职的里根是出现在我们名单中的首位总统。（全部数据见上表。）

    如果投资者预想的朋友——乔治•W.•布什是里根以来任期内股市表现最差的总统，哪位总统的任期内股市表现最好？不，不是启动减税狂欢的里根，而是在首届任期内大幅加税的比尔•克林顿。

    想想吧。股市在两届民主党总统任期中表现出色，而三位共和党总统任期内的表现则垫底。

    Finding Obama at the top isn't what I expected to see when I asked Wilshire to calculate returns by presidential administrations for me. We started with Ronald Reagan because Wilshire didn't begin tracking daily market returns with its Wilshire 5000 index until 1980. That's why Reagan, who took office in 1981, is the first President on our list. (You can find all the numbers in the table to the left.)

    If George W. Bush, the investors' supposed friend, produced the worst return of any President starting with Reagan, whose administration showed the best return? No, not Reagan, beloved in some places (and notorious in others) for kicking off our orgy of tax cuts. It was Bill Clinton, who pushed through a hefty tax increase during his first term.

    Think about it. Under two Democratic Presidents, stocks have shown the best return, while three Republicans bring up the rear.