截至上周四，美國的牛市已經(jīng)持續(xù)了八年。這比大部分專家預(yù)測的要長得多，也超出了華爾街幾個(gè)月前的預(yù)期。

今年僅過去兩個(gè)月，標(biāo)普500（S&P 500）指數(shù)就已經(jīng)達(dá)到甚至超過了華爾街許多頂尖公司預(yù)測的2017年全年目標(biāo)。去年12月，彭博社（Bloomberg）調(diào)查了美國許多重量級證券公司的分析師，得出的預(yù)測是標(biāo)普500指數(shù)會漲到2,340點(diǎn)——在今年年底。

而2017年至今，標(biāo)普500指數(shù)已經(jīng)上漲了超過6%，在3月1日最高曾達(dá)到2,396點(diǎn)，超過了預(yù)測數(shù)值。（之后指數(shù)略有下滑，上周三收盤時(shí)為2,363點(diǎn)。）特朗普總統(tǒng)上臺后，股指的增長已經(jīng)持續(xù)了很長時(shí)間，這一段時(shí)期勢頭甚至更甚。去年11月起，因?yàn)樘乩势粘兄Z減輕企業(yè)稅負(fù)，放松政策，標(biāo)普500指數(shù)的漲幅達(dá)到了11%。

整體來看，自2009月3月9日跌至當(dāng)日最低值666點(diǎn)以來，標(biāo)普500指數(shù)漲幅高達(dá)255%。根據(jù)摩根資產(chǎn)管理（J.P. Morgan Asset Management）的研究，歷史經(jīng)驗(yàn)來看，從低谷至高點(diǎn)，牛市的平均持續(xù)時(shí)間為四年半。

現(xiàn)在的問題是，這次牛市還將持續(xù)多久？已經(jīng)有許多股市巨頭認(rèn)為，股指恐怕即將迎來下跌。盡管今年頭兩個(gè)月漲勢強(qiáng)勁，但受訪的很多證券公司并未大幅調(diào)整，甚至根本沒有調(diào)整年終預(yù)測，這表明他們估計(jì)市場已經(jīng)達(dá)到或接近今年的高點(diǎn)。

彭博社3月再次對證券公司進(jìn)行了調(diào)查，他們對2017年的預(yù)測僅提高了10點(diǎn)至2,350點(diǎn)（低于股市現(xiàn)在的水平）。例如，巴克萊銀行（Barclays）就沒有調(diào)整他們2,400點(diǎn)的預(yù)期，不過他們把2017年的綜合每股收益從127美元上調(diào)到了130美元。瑞士信貸（Credit Suisse）和瑞士聯(lián)合銀行（UBS）去年12月預(yù)測今年年底的標(biāo)普500指數(shù)為2,300點(diǎn)，他們依舊堅(jiān)持自己對股指和每股收益率的推斷。

接受調(diào)查的機(jī)構(gòu)中，也有一些對股市更為樂觀。德意志銀行（Deutsche Bank）把預(yù)測上調(diào)了200點(diǎn)至2,600點(diǎn)。美國銀行（Bank of America）也上調(diào)了150點(diǎn)，他們現(xiàn)在估計(jì)指數(shù)將在年底達(dá)到2,450點(diǎn)。

標(biāo)普500指數(shù)是否繼續(xù)上揚(yáng)，很大程度取決于特朗普經(jīng)濟(jì)政策的效果。目前市場的熱情，建立在特朗普將成為企業(yè)利好的推測之上，不過最大的問題在于他想要推行的政策——包括廢除《可支付醫(yī)療法案》和稅法改革——能否獲得國會的通過。此外，稅法的改變最早也得到2018年才能看到效果，如果目前的牛市已經(jīng)把希望寄托在這些改變上，恐怕用不了多久股市的漲速就將減緩。希望總比絕望好，不過某些情況下實(shí)用主義才能笑到最后。（財(cái)富中文網(wǎng)）

譯者：嚴(yán)匡正

The current bull market in stocks celebrates its 8th anniversary on Thursday. That run has lasted far longer than most experts predicted—and it has gone farther than Wall Street forecasters expected just a few months ago.

We’re barely two months into the year, and the S&P 500 has already reached or surpassed the full-year expected targets for 2017 set by many of Wall Street's top firms. In a Bloomberg survey from December of analysts from many of the nation’s heavy-hitting brokerages, the median forecast pegged the S&P 500 to be sitting at 2,340—at the end of this year.

The index has already surpassed that mark, rising more than 6% so far in 2017 to peak at 2,396 on March 1. (It has since retreated a bit, closing Wednesday at 2,363.) This has been the acceleration of a longer surge that took hold after President Trump was elected. Since November, investors have driven the S&P 500 up 11% on the back of Trump’s promises to cut corporate taxes and ease regulations.

Overall, the S&P 500 is up 255% since hitting an intraday low of 666 on March 9, 2009. Historically, the average bull market has lasted four-and-a-half years from trough to peak, according to research from J.P. Morgan Asset Management.

Now the question is how much longer the current bull will continue. And it appears many large players in the stock markets are already anticipating some sort of pullback relatively soon. Despite the sharp growth in the market in January and February, many of the brokerages surveyed haven’t adjusted their year-end forecast upward very much, if at all, indicating they feel the market is either at or very near its peak for the year.

The median forecast for 2017 rose only 10 points, to 2,350 (below the market's current level), when Bloomberg surveyed analysts again in March. Barclays, for example, hasn’t budged off its target of 2,400, though it has moved its combined 2017 earnings per share estimate for the companies in the index up from $127 to $130. Credit Suisse and UBS, which both forecast 2,300 in December, have not changed their predictions for the index’s level or earnings per share.

There are some more optimistic views among those surveyed. Deutsche Bank has raised its forecast 200 points, to 2,600, and Bank of America has added 150 points to its prediction, bringing its estimate to 2,450.

Whether or not the S&P 500 continues its rise is likely to heavily depend on the impact of Trump’s economic agenda. The market’s run has been fueled by speculation that Trump will be a boon for business, but the biggest elements of his policy wish list—including the repeal of the Affordable Care Act and his tax reforms—have uncertain prospects in Congress. What's more, any changes in tax law wouldn’t go into effect until 2018 at the earliest; if the current bull run is factoring in those changes already, then a slowdown in the stock surge may not be far away. Hope is better than despair, but at some point pragmatism may win out.