stocks, we have been told again and again through the years, are the best long-term investment. prices go up and they go down, but give stocks enough time and they deliver returns that trounce those of bonds, real estate, commodities or any other asset class.
ha! you say. have you checked your 401(k) balance lately? since the beginning of this decade, the stock market has been a money pit. at the market's nadir in early march, stock investors had lost more than 50% since march 2000, if you factored in inflation. things have improved since then--to a mere 40% loss.
so can stocks possibly still be the best long-run investment? somewhat surprisingly, the answer turns out to hinge on what you mean by best and what you mean by long-run. the investment part actually remains pretty cut and dried. over the past two centuries, stocks have done dramatically better for investors than have bonds or any other asset class. and while, to parrot the mutual-fund prospectuses, past performance is no guarantee of future results, there are sensible economic arguments why stocks should continue to perform best in the future.
but that does not mean that buying and holding a portfolio composed mostly of stocks--the standard investing advice of the past quarter-century--makes sense for all of us. in the past few years, the mantra of "stocks for the long run" has come under fire from some respected students of financial markets. their two main critiques have to do with those terms long run and best. the first debate centers on whether you can count on stocks' long-term advantage to work out over your particular investment horizon; the second is about whether an investment as risky as stocks belongs in a retirement portfolio in the first place.
the case for stocks
first, though, a little background on stocks for the long run. the notion goes back to 1922, when a bond brokerage in new york city hired edgar lawrence smith to put together a pamphlet explaining why bonds--and certainly not stocks--were the best long-term investment. at the time, this was conventional wisdom on wall street. bonds were for investment, stocks for speculation--and, in those pre-sec days, for manipulation. but when he investigated the historical record, smith recounted later, "supporting evidence for this thesis could not be found." instead, he discovered that over every 20-year span he examined but one, stocks handily beat bonds.
in 1924, smith published the results as a book called common stocks as long term investments. it was a sensation. smith--a businessman of no great distinction up to that point--launched a mutual-fund company on the strength of his sudden fame and got an invite from john maynard keynes to join the royal economic society. his argument was that stocks would continue to beat bonds because they a) were less vulnerable to having their value eaten away by inflation and b) allowed investors to share in the growth of the u.s. economy in a way that bonds and other assets did not. these two tenets were the indispensable theoretical underpinning of the 1920s bull market.
近几年来，我们不断地被告知股票是一种最好的长期投资。价格上涨，股票下跌，但是给予股票充足的时间，它们将带来远高于债券，房地产，日用品或者其他一系列资产的利润。
哈！你会反问到。你最近查看过你的401（k）资产平稳表吗？自从十年前开始，股市就已经是一个金钱陷阱了。在今年年初三月份股市跌到最低点的时候，如果将通货膨胀计算在内的话，股票投资者自2000年3月以来已经损失了超过50%。到现在为止情况已经有所改观--但也是最起码40%的损失。
那么股票还有可能是最好的长期投资吗？有些令人惊讶的是，答案取决于在你看来最好的和长期的是一个什么概念。事实上，投资角色仍然十分固定。在过去的两个世纪里，对于投资者来说，股票远远好于债券或者是其他种类的资产。但是同时应该注意到的是，如同共同基金一样，过去的表现不能为将来的结果作担保，应该有一个明智的经济论证去说明为什么股票在未来会表现的最好。
但是这也并不意味着购买和持有由主要股票组成的一组投资--这是过去四分之一世纪以来的标准投资建议--这个建议构成了我们的判断力。在过去的几年间， “股票能够长久”的颂歌受到了一些金融市场令人尊敬的研究者的攻击。他们的两个主要的批评是针对长期和最好这些术语。第一个争论的中心是是否可以依靠股票的长期利益计算出详细的投资范围；第二个是类似于股票这种的高风险投资是否应该首先归入于收回投资。
股票之争
首先是关于股票能够长久的一点背景知识。这个概念的提出应该回溯于1922年，纽约市的债券经纪业雇请edgar lawrence smith一起来编写一本关于解释为什么债券--而非股票--是最好的长期投资的小册子。在当时，这是华尔街的传统智慧。证券用来投资，股票用来投机-- 而且，在证券交易委员会出现之前，股票是被操纵着的。但是当他研究过历史记录之后，smith 在稍后描述到，“支持这个理论的证据是找不到的。”相反，他发现在他的调查之中显示每经过一个20年的跨度，股票轻而易举地击败证券。
1924年，smith 在他的《长期投资--普通股》一书中发表了自己的研究成果。这在当时是耸人听闻的。smith--在这个理论上没有很大声望的商人--在他突然声名鹊起之时开办了一个共同基金公司，同时也被john maynard keynes邀请加入英国皇家经济学会。他认为股票将继续击败债券，原因是a）他们较少受到通货膨占的攻击而导致价值损失，b）允许投资者在某种程度上共享美国经济增长所带来的好处，这一点是债券和其他资产所不具有的。这两个原则是支撑起19世纪20年代牛市不可或缺的理论。