量化寬鬆是救經濟的萬靈丹？
摘錄自：天下雜誌 經濟學人電子報 2013/1/31
2014-01-16 Web only 作者：經濟學人
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| 圖片來源：flickr.com/photos/aresauburnphotos/ |
聯準會於12月作出了讓市場出乎意料之舉，將每月收購的債券額度從850億美元降至750億美元；央行收購政府及不動產抵押債券，即為所謂的「量化寬鬆」。有些人擔心，縮小量化寬鬆的規模會危及美國復甦，或是在新興市場製造金融不穩定。在此同時，越來越多人預期，歐洲央行很快就會提出量化寬鬆計畫以刺激歐元區經濟。但到底什麼是量化寬鬆？它應該帶來什麼效果？
維持通膨穩定是央行的任務之一，而在2008～2009金融風暴前，央行是以調整重貼現率來管控通膨。金融風暴來襲之時，聯準會、英格蘭銀行等大型央行皆大砍重貼現率以刺激經濟，但就算利率已降至接近零，還是無法帶起復甦；因此，央行開始試驗其他工具，試圖鼓勵銀行將資金投入經濟，量化寬鬆正是其中之一。
央行實施量化寬鬆的方式，就是以先前並不存在的電子現金，向銀行購買公債等證券，進而創造資金。新流入的現金增加了經濟中的銀行儲備，其增幅即為資產的購買量，所以稱作「量化」寬鬆。量化寬鬆和降息一樣，應該會藉由鼓勵銀行放款而刺激經濟，其想法為銀行獲得新資金後，會購買資產來取代它們先前賣給央行的資產，那會抬升股價並降低利率，進而刺激投資。今日，政府公債、不動產貸款、公司債等一切事物的利率，要是沒有量化寬鬆，可能都會更高。如果量化寬鬆讓市場相信，央行非常認真地想對抗通縮或高失業率，它也可以靠著提振信心來刺激經濟。
不過，量化寬鬆是好是壞仍未有定論。研究顯示它確實稍稍提升了經濟活動，但有些人擔心，大量資金流入會鼓勵魯莽的金融行為，也會讓大量資金流往無法管理這麼多資金的新興經濟體。有些人則擔心，央行出售手上的資產時，會讓利率大增並扼殺復甦。還有些人質疑，要是央行創造的現金開始快速流通，央行是否真有能力維持通膨穩定。少數銀行已經開始試驗其他的措施，例如承諾讓拆款利率長期維持於低檔；減少倚賴量化寬鬆確實是好事。（黃維德譯）
©The Economist Newspaper Limited 2014
The Economist
The
Economist explains
What is
quantitative easing?
By The Economist
From The Economist
Published: January 16, 2014
Jan 14th 2014, 23:50 by R.A.
AMERICA'S Federal Reserve surprised markets in December by starting to
"taper" its programme of monthly purchases of government and mortgage
bonds—a process known as "quantitative easing", or QE—from $85
billion a month to $75 billion. Some worry that scaling back QE could endanger
America's recovery or create financial instability in emerging markets.
Meanwhile, expectations are rising that the European Central Bank may soon
launch its own QE programme to boost the euro-area economy, where high
unemployment is contributing to deflation. But what exactly is quantitative
easing, and how is it supposed to work?
Central banks are responsible for keeping inflation in check. Before
the financial crisis of 2008-09 they managed that by adjusting the interest
rate at which banks borrow overnight. If firms were growing nervous about the
future and scaling back on investment, the central bank would reduce the
overnight rate. That would reduce banks' funding costs and encourage them to
make more loans, keeping the economy from falling into recession. By contrast,
if credit and spending were getting out of hand and inflation was rising then
the central bank would raise the interest rate. When the crisis struck, big
central banks like the Fed and the Bank of England slashed their overnight
interest-rates to boost the economy. But even cutting the rate as far as it
could go, to almost zero, failed to spark recovery. Central banks therefore
began experimenting with other tools to encourage banks to pump money into the
economy. One of them was QE.
To carry out QE central banks create money by buying securities, such
as government bonds, from banks, with electronic cash that did not exist
before. The new money swells the size of bank reserves in the economy by the
quantity of assets purchased—hence "quantitative" easing. Like
lowering interest rates, QE is supposed to stimulate the economy by encouraging
banks to make more loans. The idea is that banks take the new money and buy
assets to replace the ones they have sold to the central bank. That raises
stock prices and lowers interest rates, which in turn boosts investment. Today,
interest rates on everything from government bonds to mortgages to corporate debt
are probably lower than they would have been without QE. If QE convinces
markets that the central bank is serious about fighting deflation or high
unemployment, then it can also boost economic activity by raising confidence.
Several rounds of QE in America have increased the size of the Federal
Reserve's balance sheet—the value of the assets it holds—from less than $1
trillion in 2007 to more than $4 trillion now.
The jury is still out on QE, however. Studies suggest that it did raise
economic activity a bit. But some worry that the flood of cash has encouraged
reckless financial behaviour and directed a firehose of money to emerging
economies that cannot manage the cash. Others fear that when central banks sell
the assets they have accumulated, interest rates will soar, choking off the
recovery. Last spring, when the Fed first mooted the idea of tapering, interest
rates around the world jumped and markets wobbled. Still others doubt that
central banks have the capacity to keep inflation in check if the money they
have created begins circulating more rapidly. Central bankers have been more
cautious in using QE than they would have been in cutting interest rates, which
could partly explain some countries' slow recoveries. At least a few central
banks are now experimenting with stimulus alternatives, such as promises to
keep overnight interest-rates low for a very long time, the better to scale
back their dependence on QE.
©The Economist Newspaper Limited 2014
