????入市時機對于很多投資者而言是一門近似于算命或塔羅牌的神秘學問。理財專家總是警告散戶：不要隨便嘗試。美股上漲已進入第六年，但徘徊于歷史高點附近的牛市看起來日益脆弱。（欲了解空頭擔憂詳情，請參見2014年4月7日即將出版的《財富》（Fortune）雜志文章《股市必跌五大理由》。

????從基本面投資者、定量分析師到技術分析師都做出了各自的解讀，種種圖表都指向“死亡交叉”、與1929年股市相似以及其他表明股市走勢轉向疲軟的危險信號。但很少有人敢于預測市場是否會下跌、何時下跌、為何下跌以及下跌多少。畢竟，過去幾個月來，每個所謂的市場“頂部”最后都變成了股市上漲過程中的中間小站，空頭聽起來就像是嘟嘟囔囔的后座乘客：“還沒到嗎？”

????不過，湯姆?狄馬克是一個例外。這位精準掌握市場時機的分析人士曾經提前幾個月就準確預測了標普500指數的2011年底部，誤差僅1個點左右。本周，他告訴《財富》雜志，多頭已經來日無多。“我們即將看空，”DeMark Analytics公司CEO狄馬克預測；這家公司專門為交易員和投資者提供市場指標工具。

????他沒有止步于此。在分析標普指數的過程中，他圈出了一個未來市場的軸心點：指數1,931點。“有一點很清楚，下一輪上漲，也就是我們目前所處的這輪上漲，將是一個大頂部，”狄馬克說。“看起來這將是一個非常重要的頂部，至少要持續3個月。”他補充說，這期間跌幅至少將達到11%。

????但在下跌之前，標普500指數必須上破3月7日的歷史高點1,878點(狄馬克瞄準的是1,882點)，然后下破：“現在的回旋將迎來最后一輪猛沖，”他說。“可能還有一周時間。”

????就算你沒有聽說過狄馬克，可能也已經看到過他的研究，特別是一幅將2013年道瓊斯指數走勢與1928-1929年走勢相疊加的圖，2013年的走勢與導致大蕭條的歷史性股災之前的市場表現驚人的相似。

????“不能太把它當真，”狄馬克試圖淡化這幅圖的意義。這圖自去年秋天以來快速傳播，交易員和分析師們也在研究報告中反復提及。(狄馬克補充說，走勢在1月份出現了分化。)

????當然，狄馬克現在預測的“頂部”也可能只是牛市重現前的一個更長的停歇期，只不過不像近幾年股市經歷的停歇期那么短暫而已。有理由懷疑，市場在不遠的未來或許根本就不會調整，因為一人見之悲觀，另一人或許就見之樂觀。許多投資者仍在瞄著1月末新興市場推動的近乎6%的下跌，考慮這是否算得上一次調整。

????“在我們看來，牛市觀點仍是少數，”S&P Capital IQ首席股票策略是薩姆?斯托沃最近在一份致客戶的報告中寫道。“不完全調查樣本顯示，大量投資者仍在等待‘大調整'的到來。”因此，斯托沃變得更樂觀了：他預計標普500指數將高漲至2,030點。然后，這個指數將必須大幅下跌，跌破1,627點后他才會考慮多頭回歸。他說，直到那個時候，每次調整才是買入機會。

????狄馬克承認自己以前也犯過錯，他給了當前牛市最多再兩周的時間，兩周后就會開始回落。他說：“通常我會在它發生前就提前知道。”

????不過，不管會發生什么，大多數投資者都無法預見。那么，最佳的策略是什么？盡可能久地享受牛市，最終多頭還是會回來的。（財富中文網）

????譯者：早稻米

????Timing the market, to many investors, is a science akin to fortune-telling or tarot cards. Financial experts warn retail shareholders constantly: Don't try this at home. Yet with the market going on a sixth year of gains and hovering near record-high levels, the bull seems more vulnerable every day. (For more on those concerns, see "Five reasons the market must fall"in the April 7, 2014 issue of Fortune.)

????Investors from the fundamentalists to the quants to the technical analysts have offered their readings of the tea leaves, circulating charts pointing to the "death cross," 1929 market parallels and other red flags that signal a market retreat. Still, few dare to make predictions about if, when, why or how much the market will drop. After all, in the last few months, each supposed market top has turned out to be just another rest stop on the climb up, leaving the bears sounding like whiny backseat drivers: "Are we there yet?"

????Tom DeMark is an exception. The market timing precisionist who famously called the S&P 500's 2011 bottom within a point or so, months before it happened, told Fortune this week that the bull had just a few days left to live. "We're about to become bearish," predicts DeMark, CEO of DeMark Analytics, which provides market indicator tools to traders and investors.

????He didn't stop there. Analyzing the course of the S&P, he circled a specific point at which he expects the market to pivot: 1,931 on the index. "It’s pretty clear that this next rally, the one we're currently in, will be a good top," DeMark says. "And it looks like it's going to be a pretty important top that should last at least three months." During that time, brace for a decline of at least 11%, he adds.

????Before that happens, though, the S&P 500 must break its March 7 record of 1,878 (DeMark is eyeing 1,882) -- and then break it again: "The gyrations here are setting up for one final burst," he says. "It may be another week yet."

????Even if you've never heard of DeMark, you might still be familiar with his work -- in particular, a chart overlaying the Dow Jones Industrial Average in 2013 with stock movements in 1928 and 1929, showing an uncanny similarity to market performance just before the historic crash that led to the Great Depression.

????"That was more for entertainment," says DeMark, who has tried to play down the significance of the chart since it went viral back in the fall, and continues to be referenced in notes by traders and analysts. (The pattern, however, diverged in January, DeMark adds.)

????To be sure, the "top" DeMark foresees now may just portend a bigger breather than stocks have had for the last few years, before the bull comes roaring back. And there's reason to be skeptical that the market will correct at all in the near future, as one man's pessimism is another man's bull case. Many investors are still squinting at the almost 6% emerging markets-driven drop in late January, wondering if it even qualifies as a correction.

????"This bull market remains unloved, in our opinion," Sam Stovall, chief equity strategist for S&P Capital IQ, wrote in a recent note to clients. "Anecdotal samplings of audience opinions still point to an overwhelming number of investors who are awaiting "the big one.'" That makes Stovall all the more bullish: He expects the S&P 500 to fly as high as 2,030. The index would have to slide pretty far downhill, to lower than 1,627, before he'd consider that the bull had come home from pasture. Until then, he says, every correction is a buying opportunity.

????DeMark, for his part, admits he's been wrong before, but grants the current bull market two weeks at best before it begins to recede. "Usually I know right before it happens," he says.

????Whatever comes to pass, however, most investors won't see it coming. The best strategy? Ride the market out as long as you can, because the bull inevitably comes back, eventually.