A year ago, Bloomberg asked economists to predict how 2017 would unfurl. With the year almost over, we compared those forecasts to actual performance and, well, the results weren’t pretty.

This was the year that the textbook connection between inflation and unemployment broke down, bedeviling forecasters. So much so that our survey respondents pulled off a rare feat: missing to the upside their forecasts for both inflation and the jobless rate. Typically a miss in one direction for one of those measures accompanies a miss in the opposite direction for the other. Not so in 2017.

“We can definitely learn from that,” said Christopher Low, chief economist at FTN Financial in New York, who was among the best predictors of inflation (and among the worst on unemployment). “The thing we’re looking at here now is trying to understand where the inflation-unemployment relationship broke down.”

Only one forecast, submitted by Francois Dupuis and Francis Genereux at Desjardins Group, managed to come within 0.3 percentage point of the actual results on both unemployment and inflation. Bravo.

Inflation Mystery

How the 2017 results force economists to change the way they forecast 2018 depends crucially on whether they believe the mystery of low inflation will continue. More seem to be moving into the camp that says low inflation can’t be completely explained by transitory factors.

“I don’t think it’s a one-year phenomenon,” said Stephen Gallagher, chief U.S. economist at Societe General SA in New York. “It’s something of a new paradigm.”

To see all the individual forecasts from a year ago, click on ECFC.

For the highlights, read on. Ph.D. economists should prepare to be humbled.

Unemployment

Economists’ median forecast 4.6% Response range 3.4%-5.5% Fed’s median forecast 4.5% November unemployment rate 4.1%By November 2016, unemployment was already at 4.6 percent, about where many economists thought was its lowest sustainable rate. Few believed U.S. employers would add about 2 million jobs this year, pushing joblessness to 4.1 percent.

Inflation

Median forecast (core PCE) 2% Response range 1.2%-4% Fed’s forecast 1.8% November core PCE 1.5%If economists missed unemployment to the high side, you’d think they would miss inflation to the low side, right? Wrong. Welcome to the “mystery” of 2017, as described by Federal Reserve Chair Janet Yellen. That caught just about everyone by surprise as inflation remained disturbingly low at 1.5 percent in the 12 months through November, against surprisingly strong job gains.

What Our Economists Say “One of the biggest forecasting hurdles for 2017 was understanding the nature of the inflation soft-patch; many economists misread the signals and expected it to subside quickly, when in reality it was a reflection of weak economic performance from four to six quarters earlier. Those who attributed it to the latter were not surprised to see it endure for several months. In fact, for this very reason Bloomberg Economics expects it to stretch well into the first half of 2018.”– Carl Riccadonna, Bloomberg Economics.

Treasury Yield

In a forecast related to inflation, economists showed a similar miss when predicting the yield on 30-year Treasuries. The median estimate was for 3.34 percent at the end of 2017. It was 2.75 percent late Wednesday afternoon.

GDP

Median forecast (Q3 YoY) 2.2% Response range 0.5%-3.6% Fed median forecast (Q4 YoY) 2.1% Q3 YoY 2.3%The latest GDP figures available are for the third quarter, and forecasts were pretty solid with the median falling just a tenth below that actual result. But there’s a caveat here, as long as we assume that no one actually predicted multiple devastating hurricanes. Third-quarter figures include a small negative impact from those storms, but miss the subsequent upsurge from rebuilding in the fourth quarter. That suggests the median probably missed to the downside a shade more than the numbers show.

一年前，彭博社邀请经济学家预测2017年将会如何展开。这一年基本已经过去，把预测和实际情况进行比对，我们发现结果并不理想。

在这一年，教科书上对通胀率与失业率关系的阐述失效了，这让预测者苦恼不堪。也让我们的受访者完成了一次罕见的壮举：同时高估了通胀率和失业率。一般情况下，高估其中一项都会导致低估另一项，不过2017年并不是这样。

纽约FTN Financial的首席经济学家克里斯托弗·洛是最善于预测通胀的专家之一（也是最差的失业率预测者之一）。他表示：“我们一定可以从中吸取教训。我们现在要做的是设法弄清通胀率与失业率的联系在哪里出现了问题。”

只有Desjardins Group的弗朗索瓦·迪皮伊和弗朗西斯·吉尼罗提供的预测，与实际的失业率和通胀率差值都在0.3%以内。太棒了。

通胀率之谜

2017年的结果将如何迫使经济学家改变2018年的预测方式，很大程度上取决于他们是否相信神秘的低通胀率会持续下去。越来越多人似乎开始认为：低通胀率的情况无法完全以短期因素来解释。

纽约的Societe General SA的首席美国经济学家史蒂芬·加拉赫表示：“我不认为这种现象只会持续一年。这是一种新的范式。”

想要看看一年前每个人的预测，请访问ECFC。

想要了解重点，请继续阅读。博士经济学家需要做好准备保持谦逊。

失业率

经济学家对失业率的预测中值是4.6%，预测区间是3.4%至5.5%。美联储对失业率的预测中值是4.5%。而2017年11月的实际失业率是4.1%。在2016年11月，失业率已经达到了4.6%，许多经济学家认为这就是失业率可以维持的最低水平。几乎没人相信美国的雇主能在2017年增加大约200万个就业岗位，从而把失业率继续降低到4.1%。

通胀率

（核心个人消费开支指数）预测中值是2%，预测区间是1.2%至4%。美联储的预测值是1.8%。而2017年11月的实际核心个人消费开支指数是1.5%。经济学家如果高估了失业率，那么他们就会低估通胀率，没错吧？错。正如美联储的主席珍妮特·耶伦所说，欢迎来到“谜一般”的2017年。在工作岗位数量强劲增长的情况下，通胀率令人困扰地在截至去年11月的一年里保持了1.5%的低值，这让所有人感到惊讶。

我们Bloomberg Economics的经济学家卡尔·里卡唐纳表示：“2017年预测的最大困难之一，在于理解通胀阶段性疲软的本质；许多经济学家误读了信号，认为这种疲软会迅速消退，而实际上它是对过去四至六个季度经济表现低迷的反映。如果把它归因于后者，看到疲软现象持续了几个月，就不会感到惊讶了。实际上，正因为此，Bloomberg Economics预测这种情况将继续持续到2018年上半年。”

国债收益率

在与通胀率有关的预测中，经济学家类似地高估了30年的国债收益率。他们对2017年底国债收益率的预测中值是3.34%。而上周三近傍晚时分，国债收益率仅有2.75%。

国内生产总值

预测中值（第三季度同比增长率）为2.2%，预测区间是0.5%至3.6%。美联储的预测中值（第四季度同比增长率）为2.1%。2017年第三季度同比增长率为2.3%。目前可以获得的最新GDP数据是2017年第三季度的，而预测中值相当准确，仅比实际值低了十分之一。不过这里需要提个醒，我们认为没人真正预测到了2017年会发生数次毁灭性的飓风。这些风暴对第三季度的数据产生了微小的负面影响，而第四季度的重建又会带来GDP的上扬。这意味着预测中值与实际值的偏差，比数字显示的差距更大。（财富中文网）

译者：严匡正