在本輪美國牛市即將迎來7周歲生日之際，讓我們先別忙著慶祝，首先應該感嘆一下，這一輪持續(xù)時間巨長，已進入晚期的牛市對我們來說究竟有多“坑”。

標普500指數(shù)自2015年5月在2135點見頂以后，一路震蕩下跌15%，最近略有回彈，幅度約在一半左右，這似乎印證了一些樂觀人士的觀點——本輪牛市不僅沒有結束，反而還有繼續(xù)上升的空間。有些觀點認為，最近的跌后小漲說明人們并未對本輪牛市失去信心，而且許多投資者才剛剛開始持幣入市。然而事實恰恰相反，股市已經(jīng)過度“得寵”，目前的短暫繁榮只是熊市的序曲。

來看看證據(jù)：在任何時期，如果股價相對于收益過高，未來的投資展望都是負面的。目前，經(jīng)濟學家席勒的周期調整市盈率（CAPE）已達25.3倍。要想衡量股價是高還是低，相對于大多數(shù)投資者都在使用的傳統(tǒng)市盈率計算法，CAPE是一個要好得多的工具——當然席勒市盈率本身也正變得越來越流行。CAPE基于扣除通脹因素的10年平均利潤進行計算，熨平了收益的階段性暴漲。

目前，席勒市盈率已經(jīng)達到25倍的高位，這個數(shù)值要遠遠高于上世紀16倍的平均值。這說明股市不僅并未“失寵”，而且比歷史水平高出56%。

如果投資者還在買入，或者持有一個周期調整市盈率高達25倍的股票組合，那么5到10年后，這些投資者將面臨什么樣的光景？

需要指出的是，在美國證劵史上，CAPE很少達到這樣的高位。1928年11月，CAPE首次達到25倍——至少記錄顯示是這樣。而在接下來的10年，股票價格一路下跌了43%。

1966年1月，當標普500指數(shù)達到93點時，CAPE再創(chuàng)幾十年來的最高紀錄，達到24.1倍。在接下來的10年里，標普500指數(shù)起起伏伏，始終毫無起色，到1976年初仍收于90點，下跌3.2%。

如果你在高位買進股票，災難未必一定會在10年后爆發(fā)，但爆發(fā)災難的風險依然會存在。1996年8月，CAPE再次達到25倍，而股市仍在繼續(xù)高歌猛進。10年后，很多投資者都賺得盆滿缽平。到2006年勞動節(jié)前后，投資者的年收益（包括股利）已經(jīng)達到8.5%。接下來不出一年，美股就出現(xiàn)了大跌，并最終導致1996年夏天以來積累的大部分收益蒸發(fā)殆盡。

有些投資者深曉“以史為鑒可以知興替”的道理，在股市高位時持幣觀望，而選擇在2008年金融危機到2009年年中的“大拋售”之后這類時機入市抄底。大錢就是這樣賺來的。這種時期之后，往往會有一個牛市。要知道，老牛不會自己變成小牛，而是會直接死掉。這就是將要發(fā)生的事情。這一輪牛市死得越早，我們就將越快看到新一輪交易的興盛，對投資者來說，那個時候也會安全得多。（財富中文網(wǎng)）

譯者：樸成奎

審校：任文科

Instead of celebrating the bull market’s seventh anniversary, let’s mourn the ways that, at this advanced stage, long-running bull markets are bad for us.

After peaking at 2,135 in May, the S&P 500 SPX 0.00% tumbled 15% before recently rebounding, snapping half way back, and bolstering the optimists’ view that the bull isn’t just intact, but still has legs. What recent mini-bust and even smaller rebound does not show, as some are saying, that the bull market remains unloved, and investors are just starting to get on board. On the contrary, stocks are over-loved, and the current boomlet is simply makes things worse.

Here’s the proof: In any period when prices are high relative to earnings, the future outlook for investors is bleak. Right now, the economist Robert Shiller’s cyclically-adjusted price-earnings ratio, or CAPE, stands at 25.3. The CAPE is a far better measure of whether prices are cheap or rich than the price-to-earnings ratio that most investors use—though the Shiller P/E has become more and more popular—because it smoothes the volatile fever chart of earnings by using a ten-year average of profits, adjusted for inflation.

Today the Shiller P/E stands at 25. That’s far above the average of around 16 for the past century. Stocks aren’t unloved. They are 56% more cherished than they generally have been historically.

So how do investors fare 5 and 10 years later when they’re buying in, or simply holding, a diversified portfolio of stocks with an adjusted P/E of 25?

It’s important to note the CAPE has seldom reached these heights in the annals of equities. In November of 1928, it reached 25 for the first time, at least on record. Over the next decade, stock prices dropped 43%.

In January of 1966, it hit a multi-decade record of 24.1 when the S&P 500 reached 93. It bobbed and weaved over the next decade, but went nowhere, finishing at 90 at the start of 1976, for a loss of 3.2%.

Disaster isn’t always lurking ten years out if you buy at high prices. But it’s still lurking. The CAPE reached 25 again in August of 1996—and kept soaring from there. Ten years later, investors had done pretty well. Around Labor Day of 2006, they’d registered annual returns, including dividends, of 8.5% a year. But the big slide began less than a year later, and it eventually destroyed most of the gains since the summer of ’96.

Investors who learn from history pounce after a gigantic selloff, like the one following the financial crisis in 2008 through mid-2009. That’s when the big money gets made. A bull market follows those periods. Old bulls don’t turn into young bulls, they die off. That’s what’s going to happen. The sooner it does, the sooner we’ll see a whole new galaxy of bargains, and a much less dangerous time for investors.