Ten years ago, I called anyone buying into Google’s much hyped IPO a “sucker.” My bottom line, which I helpfully broke out into a separate paragraph titled “My Advice” in my Money magazine article was “stay clear.” Man was I wrong.

    In fact, few investing calls, since the beginning of time, have been more wrong. Leading economist Irving Fisher calling stocks cheap in 1929. And then there’s me.

    Google’s shares started trading at $50, adjusted for a2-for-1 splita few years later. I said they were worth less than half that, around $20. And I was pretty sure they would soon nosedive to that price. They never did.

    A decade later, Google’s shares now trade for $586. That’s a 1084% return, roughly 10 times what the stock market did at the same time. If you had invested $10,000 in Google then, you would now have $118,400, or $97,000more than what you would had if you invested the same money in the S&P 500. You’re welcome!

    So why was I so utterly wrong about Google? Can I learn anything about investing from this call?

    First of all, trying to come up with an exact price for what a company is worth is the true suckers game. To come up with my $20 a share for Google, I used what Wall Streeters and finance professors call a discounted cash flow model. And I sought out the advice of New YorkUniversity economics professor Aswath Damodaran, who wrote a textbook about how to value companies, to do it. Estimate all the money you think a company is going to generate over the next decade (because try to estimate beyond that and you are bound to look pretty silly), and then figure out what, based on future inflation, that cash flow would be worth today. And presto, you will know what Google, or any company should be worth.

    Ok, so there were a number of ways to mess this up, and I did all of them. My first mistake was to assume that Google’s sales growth would be a stable 30% a year. Online advertising was increasing, and I figured Google would get a slice of that. What I didn’t understand was that Google wouldn’t just get a slice, but nearly all of it. As a result, Google’s revenue has grown an average of 50% a year over the past decade.

    Also, I thought there was a high probability that I was overestimating how profitable Google could be. I said there was a strong possibility that Google would end up with Netscape in the internet graveyard. Based on its current profitability, I said Google could earn $48 billion over its lifetime. But that, I said, was unlikely. What’s more, inflation would eat up the value of a lot of those profits. So I used a discount rate of 15%, per year, to figure out that the value of those profits was more like $15 billion.

    Not even close. Google’s actual cash flow over the past decade has been just over $90 billion, and inflation has been basically non-existent.

    十年前，谷歌（Google）进行了首次公开募股。那时，我认为这里面充满了虚夸成分，并把所有购买谷歌股票的人称为“傻蛋”。我还特意在我为《Money》杂志撰写的文章中单独加了一段文字，并以“我的建议”为题写道“别碰这只股票”。事实证明我错了。

    实际上，从始至终很少有谁给出的投资建议像我错得这么离谱：只有著名经济学家欧文•费舍尔在1929年（大萧条时期）曾称股市前景一片光明，之后便是我了。

    谷歌上市后的股价为50美元，几年后股票“一拆二”。当时我说他们股票的实际价值连这个数的一半都不到，大约在20美元左右——我当时非常肯定谷歌股价将会暴跌到这个价格。但是这种情况却没有发生。

    十年后，谷歌的股价为586美元，回报率高达约1084%，是同期股市回报率的10倍。如果那时你在谷歌投资了一万美元的话，那么现在你的一万美元就变成了118,400美元，比你把钱投给标普500所赚的还要多上97,000美元。听了我的你就亏了！

    为什么我对谷歌的判断错的这么离谱？我能从这件事上学到什么吗？

    首先，试图预估一家公司的确切股价是极其愚蠢的。我之所以给出谷歌每股20美元的价格，是因为我运用了那些华尔街和财经专家所谓的现金流贴现模型。我还向纽约大学经济学教授阿斯沃斯•达摩达兰求教，因为他写了一本如何给公司估值的书。预估公司在以后十年间（因为试着预估更远的时间只能让你显得很蠢）盈利的总额，然后参照未来通胀预期得出现金流当前价值。这样，你很快就能算出谷歌或者其他任何公司的市值。

    好吧，有好多方法可以把计算结果搞得一团糟，而我则都试了个遍。我第一个失误是，预估谷歌销售额将会保持年均30%的稳定增长。在线广告市场在不断增长中，因此我估计谷歌将会从中分一杯羹。但是我万万没有想到的是，谷歌得到的哪里只是一杯羹，它得到的几乎是全部。事实上，谷歌的收入在过去十年间保持了年均50%的增长。

    并且，我一度还认为我很可能高估了谷歌的盈利能力。我曾声称谷歌极有可能和网景公司（Netscape）一样葬身于互联网的发展洪流中。基于它当时的盈利能力，我预计谷歌最多能挣480亿美元，但我断言这几乎不可能实现。而且，通货膨胀将吞噬其大部分利润。因此我用每年15%的折现率，估算出这些利润的价值约为150亿美元。

    这与事实相去甚远。谷歌在过去十年间的实际现金流超过900亿美元，并且通胀基本上不存在。

    If I had gotten that number correct, and trusted it, I still wouldn’t have predicted that Google’s shares would be near $600 by 2014. But I would have thought the stock was a buy back at $50.

    Second, some companies do live up to their hype. Actually, probably more than most of us expect. Damodaran, who I called up to chat about our decade old folly, said not to be so down on trying to value companies. He thinks you will be wrong 20% of the time. That seems low to me. A number of companies that I thought were successes a decade ago have faltered. But I can’t think of eight high profile busts.

    The companies that are still around a decade from now will probably perform better than expected. So the better question is not what the company will earn over the next ten years, but will it be around ten years from now. And then just assume if it is, it will do much better than you expect.

    Lastly, the companies that succeed are always going to be worth more than you think they are worth. That’s the nature of the stock market. We’re all chasing the same few stocks. And the market moves in herds. We think of the market and all the buying and selling as a way to come at the exact price a company is worth. That’s the efficient market hypothesis. Instead, the market for stocks works like any other market. The good stuff always costs more than you think it should. And the bad stuff is always overpriced.

    Bruce Greenwald, Columbia’s reigning expert when it comes to investing, says I shouldn’t feel so bad about being so wrong about Google. A decade ago, the search business still seemed in flux. So again, I would have had to have known that Google wasn’t going away, and that it along with online advertising was going to take over the advertising world. In short, I had to know that Google was not just another Internet company, but the Internet company. I did not know that.

    So here’s what I think I have learned: A decade ago, I thought price was the most important thing when it came to investing in stocks. That doesn’t seem right to me. The lesson of Google is that the most important thing when it comes to investing is picking the right companies. Get that right, and the price you pay for their shares is always going to be a good bet.

    How do you know what companies will succeed? That leads me to my second, and more useful, lesson from my experience with Google: Buy index funds. I don’t know the future. Do you? And you kind of have to know the future really well to pick individual stocks. So don’t do it. Just buy the S&P 500. If the companies are successful, like Google, they will end up in the index eventually.

    A few months after the IPO’s success, when Google’s stock had risen to the equivalent of $61, I again advised avoiding the stock. Instead, I said to buy eBay . Wrong, again. eBay’s stock is up a pathetic 17% since then. Although I also said to avoid the shares of Yahoo –a good call, but not enough to get me off the hook for the worst investment call of all time.

    即使上述的数字都是正确的，我也无法依靠这些数字预测到谷歌的股价会在2014年达到近600美元。但是，我还以为股票的回购价在50美元。

    第二，一些公司确实能做到名符其实，事实上，可能比我们预期的还要好。我同达莫达兰联系，聊起这个10年前的错误。他告诉我不需要为此太过介意，他认为在公司估值问题上，失误率一般都在20%左右。对我来说绝不止这个数字。很多在十年前被我视作成功的公司现在都已经辉煌不再。不过，其中倒是也没有八家公司破产。

    这些公司在未来十年的表现可能会超出预期。因此，我们应该问的并不是一家公司在下个十年到底能挣多少钱，而是从现在开始十年后，它是否还会存在。假设它依然存在，那么它会比你预计的还要成功。

    最后，那些成功的公司往往比你想象的还要有价值，这就是股市的本性。我们都在追逐同一批为数不多的股票，市场永远在随大流。我们认为市场和所有的买入卖出都是建立在对公司价值的精确估值上。这就是有效市场假说。但事实正好相反，股票市场和其他市场一样，好的东西往往比你的预估更有价值，而坏的东西则会被过高估价。

    哥伦比亚大学（Columbia）权威专家布鲁斯•格林沃德说我并不应该因为错估了谷歌公司而这么沮丧。十年前，搜索市场在不断变化，好多东西还不完善。但是，我本应该知道谷歌公司并不会垮掉，而且随着在线广告蓬勃发展，该公司就会掌握整个广告行业。简言之，我应该明白谷歌公司并不只是一家普通的互联网公司，它是一家领先业界的、独一无二的互联网公司。而我当时并不知道这一点。

    我从中学到的东西是：十年前，我认为价格是投资股市时最重要的元素。现在我觉得这种理解是不正确的。而谷歌给我上了生动的一课，使我深刻意识到，在投资时最重要的是要选择正确的公司。只要选择正确，你买的股票就就不会让你失望。

    你怎么才能知道哪些公司会成功呢？这是我要阐释的第二点，这也是更为有用的一点。我从谷歌案例上学到的是：购买指数基金。我无法预知未来，你能么？想要选择好的股票，你必须有准确预测未来的能力。因此别费力去预测了，你只需要买标普500上的股票。如果有公司终会成功，比如谷歌的例子，那么放心，它们最终会出现在指数上。

    谷歌上市成功的几个月后，其股票攀升到约61美元，那时我再一次建议大家别碰这只股票。相反的，我还建议去买eBay。我又错了！eBay的股票从那时起只升值了17%。我还曾建议别去买雅虎（Yahoo）的股票，这个倒是对的，但是这不足以抹去我曾经给出史上最差投资建议的事实。（财富中文网）