????就經濟擴張期而言，美國這次的持續時間可謂相當“長”。二戰以來，兩次衰退之間的平均間隔約為58個月。而本輪經濟周期已經延續了81個月，人們自然想知道經濟會不會馬上滑坡。

????同時，一組令人擔憂的海外經濟數據顯示，新興市場的問題開始影響發達國家：

????·設在威斯巴登的德國聯邦統計局10月8日公布，作為歐洲實力最強的經濟體，8月份德國出口額環比下降5.2%。

????·英國經濟增速一直高于大多數發達國家，但近期數據表明，英國8月份建筑業產值下降4.3%，創2012年以來最大單月跌幅。

????·日本的情形也好不到哪里去。今年夏季日本工業產值大幅下降，有些人據此認為這個全球第三大經濟體已經重新陷入衰退。

????美國前財長拉里·薩默斯也認為今后全球經濟將遇到更多麻煩。上周四，薩默斯在一篇題為《全球經濟著實危險》的專欄文章中指出，經濟越發失衡，人口增長緩慢，需要加強金融監管，而且眼下的創新并沒有非常明顯的勞動密集型特征，這些都表明經濟增速將放慢。

????花旗集團首席經濟學家威廉·布伊特也提出了全球經濟衰退是否即將或已經到來的問題。

????布伊特對全球經濟衰退的定義和對美國這樣一個單一國家的經濟衰退的定義不同。雖然他覺得全球經濟增速并未下降，但他確實認為，經濟增長率已經低于其潛在增速，而且問題正在變得越發嚴重。上周，他在寫給客戶的報告中指出：

????“盡管全球實際產出呈正增長態勢，但已經低于其潛在增速。我們對后者的估算值為3%，這就是說產出缺口正在擴大。因此，如果產出增長率低于潛在增速的情況再持續一年，就意味著按我們的這兩項標準衡量，全球經濟可能會重新陷入衰退。”

????薩默斯認為，出現令人擔心的經濟數據只是經濟陷入困境的開始，因為引發他所說的“長期經濟停滯”的因素都不會很快消失。他指出，2008年以來，“新興市場的強勁表現”是全球經濟增長的唯一動力。然而，目前投資正在迅速向發達債券市場回流，從而進一步壓低利率。薩默斯寫道：

????“沒時間洋洋得意了。有人認為經濟增長緩慢只是2008年金融危機的短暫后遺癥，這種想法實在荒謬。最新數據表明，美國經濟增速正在下降，歐洲和日本已經開始減速。全球經濟瀕臨停滯時的最主要危險就是衰退。”

????薩默斯在文章中稱，富裕國家需要率先采取防范措施。第一步就是將利率保持在接近于零的水平，直到出現明顯的通脹跡象。但更重要的是執行“擴張性財政政策”，或者說像美國、德國和英國政府那樣，借助全球經濟形成的低利率環境來籌措資金，并將其投入基礎設施領域。

????可惜的是，對薩默斯的擁躉來說，政府支出看來不會在短期內上升。多年來，德國政府一直不同意提高支出水平，美國和英國的保守黨也在竭盡全力地削減預算，而不是提高開支水平。

????薩默斯的觀點還面臨著另外一個不利因素，那就是美國并沒有像世界其他地區那樣出現經濟放緩跡象。當然，9月份就業數據沒有達到預期，一年來標普500指數也跌跌不休。但在2015年，美國平均每個月能創造差不多20萬個就業機會，房地產交易和新開工面積均保持上升勢頭，汽車銷量也剛剛刷新10年來的最高紀錄。

????大多數經濟學家仍認為，至少一年內美國不會陷入衰退。上個月，彭博采訪了31位經濟學家，其中只有八人預計美國將在2018年以前出現經濟衰退。但考慮到新興市場的經濟問題已經傳導到日本和歐洲，我們有理由對主流觀點保留一點懷疑。（財富中文網）

????譯者：Charlie

????校對：詹妮

????As far as economic expansions go, our’s is pretty long in the tooth. Since World War II, the average length of time between recessions is about 58 months. With the current cycle clocking in at 81, it’s natural to wonder if the next downturn is imminent.

????Meanwhile, a worrying level of data from abroad shows that the troubles in emerging markets are beginning to affect the developed world:

????? In Germany, Europe’s strongest economy, exports fell 5.2% in August from the previous month, the Federal Statistics Office in Wiesbaden announced on Thursday.

????? In the U.K., where growth had been outstripping most of the rest of the developed world, recent data shows output in Britain’s construction sector plunged by 4.3% in August, the sharpest monthly drop since 2012.

????? In Japan, things don’t look much better. Serious declines in industrial output over the summer suggest to some that the world’s third largest economy has already fallen back into recession.

????Former Treasury Secretary Larry Summers also sees global economic trouble up ahead. In an op-ed published on Thursday titled “The global economy is in serious danger,” he argues that rising economic inequality, slowing population growth, and the increased need for financial regulation, and the fact that the innovation that is taking place isn’t very labor intensive all point to a slowdown.

????Another analyst asking whether we are headed for, or already in, a global recession is Willem Buiter, Chief Economist at Citigroup.

????Buiter relies on a different definition of global recession than what is used to define such an event in a single advanced economy like the United States. While he doesn’t see global growth contracting, he does believe that growth has already fallen below its potential, and that the problem is only going to get worse. In a note to clients this week, Buiter writes:

????“Actual global output growth, although positive . . . is already below likely potential global output growth, which we estimate at 3%, meaning that the output gap is widening. Another year of sub- potential growth would therefore imply that the world economy would probably be back in recession according to both our criteria.”

????Summers thinks the worrying economic data we are seeing is just the beginning of troubling economic times, because none of the factors contributing to what he has called “secular stagnation” are set to dissipate anytime soon. He argues that the only thing propping up the global economy since 2008 has been “the strength of emerging markets.” But investment there is quickly reversing course, finding its way back into developed bond markets, pushing interest rates even lower than they already are. Summers writes:

????“This is no time for complacency. The idea that slow growth is only a temporary consequence of the 2008 financial crisis is absurd. The latest data suggest growth is slowing in the United States, and it is already slow in Europe and Japan. A global economy near stall speed is one where the primary danger is recession.”

????In his op-ed, Summers argues that the wealthy world needs to take the lead in preventing this outcome, first by keeping interest rates near zero until there is a clear sign of inflation. More important, however, is to implement “expansionary fiscal policy,” or borrow at the low rates the global economy is offering governments like the U.S., Germany and the U.K. to invest in infrastructure.

????Unfortunately for those who agree with Summers, more government spending doesn’t appear to be coming anytime soon. For years, Germany has resisted calls to spend more, while the conservative parties in the United States and the U.K. are doing their best to cut budgets, not expand them.

????Further hurting Summers’ case is the fact that the United States is not seeing the same signs of slowing growth as the rest of the world. Sure, September’s jobs report was disappointing, and the S&P 500 has been moving sideways all year. But job growth in 2015 still sits at just under 200,000 new positions per month, while home sales and housing starts figures have been on the upswing. And auto sales just hit a new 10-year high.

????Most economists still see the U.S. avoiding recession for at least another year. Last month, Bloomberg surveyed a group of 31 economists, and eight predicted that a recession would hit the United States before 2018. But as troubles in emerging markets bring economic woes to Japan and Europe, it makes sense to question the conventional wisdom.