對于美國股市的抨擊之一是：2009年以來利潤普遍增加，導致估值過高成為了一個市場上波及廣泛的長期問題。該理論認為，我們無處可躲。

而一個弱化了大型公司影響力的估值工具使這種危險進一步加劇。這個工具就是標普500公司股價收入比的中值。它關注股指的中值，弱化了蘋果（Apple Inc.）和埃克森美孚（Exxon Mobil Corp.）等巨頭的重要性。Leuthold Group計算的數據顯示，該指標如今為2.63，而在2000年2月只有1.23。

與公司市值相比，該指標呈現出的估值情勢更加危險。以此來看，標普500指數的市銷率達的2.2倍，與18年前的峰值相同。

Leuthold的首席投資官道格·拉姆西認為其間的矛盾凸顯了當今年代和泡沫年代的關鍵差異。那時，估值過高的現象主要集中于科技巨頭。而如今，每只股票都很貴。

拉姆西在上周的紀要中寫道：“去年，我們標出了標普500公司的市銷率——它已經達到了2000年的泡沫水平，這是‘我們數據庫中最令人恐懼的一張表’。這個增加的數據讓一張本來就令人擔憂的表格變得不適合出現在供家庭成員閱讀的刊物上。”

本月可能標志著美國股市史上最長的牛市，隨之而來的警告越來越多，而Leuthold的研究報告則是這些警告中的最新一條。隨著美國牛市進入第10年，利潤到達頂峰、利率提高、全球貿易緊張等各種因素都被看跌者視為股價跳水的可能原因。

截至紐約時間8月7日上午11點，標普500指數連續第四天上漲，距離今年1月創下的歷史最高點僅有0.5%的差距。

市銷率的中值在過去五年里都高于2000年，而市場還在推動著它不斷走高。由市值加權的估值還沒有達到泡沫水平，但Leuthold已經開始敲響警鐘了。

誠然，拋開收入來看，成本削減、股份回購和減稅都會影響評判公司的標準，如此一來，股市的估值就會合理許多。標普500公司21倍的市盈率仍然只有互聯網泡沫時代市盈率的三分之二。

不過，對于一個讓看漲者得到安慰的現象，Leuthold的數據提出了疑問：更多人參與到股市中來，是市場之幸，還是市場之殤？

目前來看，許多人認為有更多人參與股市是一個健康的跡象，意味著股市的上漲有著堅實的基礎。不過在一切都上漲的情況下，市場中幾乎沒有剩下的價值了。

拉姆西表示：“估值過高的普遍性的確有助于解釋價值投資經理如今的悲觀情緒。相對于20世紀90年代的增長勢頭，他們經歷過一段股價弱勢時期。但長期的忍耐并未讓他們在股市上真正撿到便宜——就像1999年和2000年那樣。”（財富中文網）

譯者：嚴匡正?

A knock against stocks is this: that the pervasiveness of gains since 2009 has made overvaluation a chronic problem across a broader-than-usual swath of the market. There’s nowhere to hide, the theory holds.

A valuation lens that tamps down the influence of the biggest companies highlights the danger. It’s the median price-to-sales ratio for members of the S&P 500. The measure, which de-emphasizes giant companies like Apple Inc. and Exxon Mobil Corp. by focusing on the center of the index, stands at 2.63 right now, compared with 1.23 in February 2000, data compiled by Leuthold Group showed.

The data reveal a more perilous valuation picture than one would get by looking at gauges that are skewed by a company’s market capitalization. By that approach, the S&P 500 traded at 2.2 times sales, in line with the peak levels seen 18 years ago.

To Doug Ramsey, Leuthold’s chief investment officer, the contrast highlights a key difference between now and the bubble years. Back then, overvaluation was highly concentrated to tech giants. Right now, everything is expensive.

“For the last year, we have labeled the S&P 500 price/sales ratio – which has returned to its Y2K bubble levels – the ‘scariest chart in our database,”’ Ramsey wrote in a note last week. “The addition transforms an already alarming chart into one that’s almost unfit for a family-friendly publication.”

Leuthold’s study adds to a growing list of caveats for a bull market that could become the longest in history this month. As the advance entered its 10th year, bears have touted everything from peak profits to higher interest rates to global trade tensions as reasons to bail.

The S&P 500 rose for a fourth day as of 11 a.m. on August 7 in New York, about 0.5 percent away from topping its all-time high reached in January.

The median price-sales ratio has been higher than it was in 2000 over the past five years and the market kept going higher. It’s not until the cap-weighted valuation reached the bubble level that alarms started ringing at Leuthold.

To be sure, viewed against earnings, a business yardstick that can be influenced by things such as cost cutting, share buybacks and tax cuts, stock valuations look more reasonable. At about 21 times profits, the S&P 500’s multiple is still about a third below levels seen in the dot-com era.

Yet Leuthold’s data raised a question about a phenomenon that equity bulls have found comfort in: Is wider stock participation a blessing or a curse for the market?

For now, many see wider breadth as a healthy sign that the advance is on a solid footing. But, with everything going up, that leaves little value left in the market.

“This breadth of overvaluation certainly helps explain today’s level of despondence among value managers,” Ramsey said. “They’ve suffered through a period of underperformance relative to growth and momentum that rivals the 1990s. But the long period of penance has not rewarded them with any truly cheap pockets of the stock market – like it did in 1999 and 2000.”