歐洲和日本的利率為負，這種情況在美聯儲採取進一步加息行動之前會維持一段時間。因此，如果經濟再度陷入低迷，各國央行調整利率水平、放寬貨幣政策的餘地就很小了。
一種方法是“直升機撒錢”，即央行增印鈔票來刺激經濟，或是直接補償給消費者或是資助公共事業。這個方法旨在刺激需求並增加通脹，因為很多國家當前的通脹率都低於預期水平。金融時報的Martin Wolf近日對這一觀點表示了贊同。對沖基金經理Ray Dalio也認為“直升機撒錢”是個好辦法。
這個方法為什麼有效呢？經濟學家Simon Wren-Lewis指出：“將印刷的鈔票補償給消費要比購買政府債券(QE)好得多。因為消費者會把錢花掉，而政府債券會降低長期利率來刺激經濟。第二種方法已經嘗試過了，而且不太成功。所以為什麼不試試第一種方法呢？”
但這種方法若想實施需要經過政府的嚴格審批，而且會導致非常現實的問題，所以無論是德國政府還是美國國會都很難批準。但“直升機撒錢”更吸引左翼政客們，因為這是一種再分配性政策，或是使所有人受益，或是投資到基礎設施中，降低失業率。
那麼市場會如何反應？花旗集團Steven Englander試圖從一份調查報告中得出結論。他將美國假象為一架直升機，結果顯示，收益曲線會變陡峭（長期債券收益會增加），證券表現會改善（尤其是依賴於經濟增長的週期性股票）。出人意料的是，他認為美元的表現會變好，強勢增長的美元和高收益的債券會吸引國外資本。
最終效果如何很大程度上取決於刺激的大小和方法。適當的刺激會使通脹和需求略有提升，而不會導致魏瑪式惡性通脹。這種增長是永久性的嗎？還是說政府會在未來幾年内取消這項政策之前先行通知？雖然能夠安撫市場情緒，但是某些消費者會開始省錢、減少支出，這將降低刺激的成效。還有一種可能性是大量資金被投入進口產業中，如：平闆電視和外國節日等。這會導致經常項目赤字增加，對貨幣產生潛在的消極影響。此舉可能會刺激國外經濟，允許他們自由乘坐這架直升飛機。所以多國同時採用“直升機撒錢”是一個好辦法，就像雷曼倒閉之後的財政刺激一樣。
當然，潛在的阻礙也有不少。如果債券價格下跌，那些購買了超低收益債券的投資者會怎樣？養老基金倒是沒問題，因為負債會隨之減少，但是銀行的問題就大了。投資者很可能受到驚吓，政府支出貨幣化的禁忌也會被打破。如果選民喜歡的無效投資都能由央行來買單，那政府煞費苦心地增加稅收、削減支出又是為了什麼呢？
這個問題比支持者們想象的要困難得多。金融市場的Matthew Klein認為：“央行直接向家庭賬戶轉賬的方法簡單易行，這樣一來，如何處理新造錢幣的問題就無需任何政治辯論了。”
但是約有1000萬美國家庭和150萬英國家庭沒有銀行賬戶，他們中大多數人的生活都很貧苦。除此之外，你還要排除一些人嗎？罪犯？移民者？你可以想象，這會引起軒然大波的。如果某些人用這筆額外的收入吸食可卡因或是飲酒狂歡，一定會上新聞頭條的。用這筆錢建造學校和醫院可能更穩妥些。
What if the helicopters took off?
INTEREST rates are negative in much of Europe and Japan, and it may be a while before the Federal Reserve follows up December's quarter-point increase in rates. So that doesn't leave the authorities with a lot of room, in terms of altering the level of rates, to ease policy if another downturn hits.
One option would be "helicopter money" - the central bank could create the money to fund a fiscal stimulus, either by direct transfers to consumers* or by funding public projects such as infrastructure. The idea would be to stimulate demand and potentially increase inflation, which is below target in many countries. Martin Wolf of the FT recently praised the idea, and he hobnobs with the world's policymakers on a regular basis. The hedge fund manager Ray Dalio is another who thinks that helicopter money is the next option.
Why might this be helpful? The economist Simon Wren-Lewis has said there is
an understandable view that it would be better to print money and give it to consumers who would spend it (helicopter money), rather than using it to buy government debt (QE) which may reduce long term interest rates which may help stimulate the economy. The second route has been tried and has not been that successful, so why not try the first route?
It is hard to see any central bank doing this without very explicit approval from their government, and that creates the very practical problem that neither the German government nor the Republicans in the US Congress would ever agree to such a thing. Helicopter money has more appeal to leftwing politicians since it can be classed as a redistributive policy. Either all citizens would get the same payout or, if the money is spent on infrastructure, unemployment would fall.
So how would the markets react?Steven Englanderof Citigroup tries to look through the implications in a research note. He works on the assumption of a US helicopter drop (although Europe or Japan look more likely candidates). The yield curve would steepen (long-dated bond yields would rise), and equities would do well (particularly cyclical stocks on the grounds that the effect would be to stimulate the economy. Surprisingly, perhaps, he thinks the effect would be positive for the dollar; stronger growth and higher bond yields would suck in foreign capital.
A lot would surely depend on the size of the stimulus and how it would be framed. A modest stimulus might lift inflation and demand a bit, without leading to talk of Weimar-style hyperinflation. Would the expansion be permanent or would the government pre-announce a plan to "claw it back" in a few years' time? That might reassure the markets but some consumers might save the money to meet the tax bill, making the stimulus less effective. There is also a risk that a lot of money might be spent on imports - flat screen TVs and foreign holidays. That might cause the current account deficit to soar, potentially negative for the currency. The effect might be to stimulate overseas economies, allowing them to free ride on the helicopter. So one answer would be to get lots of countries to pursue helicopter money simultaneously, rather as they agreed to use fiscal stimulus after Lehman collapsed.
There are, of course, lots of potential snags. What would happen to those investors who bought bonds at ultra-low yields if bond prices plunged? No problem for pension funds (whose liabilities would fall too) but it might be a problem for banks. And it is possible that investors might take fright; that monetisation of government spending might be a broken taboo too far. After all, what government would ever want to raise taxes or cut spending, if lots of voter-friendly boondoggles could be financed by a tame central bank?
* This might be more difficult than proponents assume. Matthew Klein at the FT suggests:direct deposits into household accounts offered at the central bank. It’s simple and doesn’t require any political debate about how best to spend the newly created money.
But around 10m US households and 1.5m British adults lack a bank account, many of whom will be poor. Is it fair to exclude them? By the same token, these people may not be on the electoral roll. And would you deliberately exclude people? Prisoners? Immigrants? One can only imagine the political furore that could be created, or the headlines if some people spend the proceeds on cocaine or a drinking binge. Building lots of schools and hospitals might be the safer option.
本文翻譯由兄弟財經提供
文章來源：http://www.economist.com/blogs/buttonwood/2016/03/monetary-policy-and-markets