隨著日本央行在2月29日宣佈通過存款利率啟動負利率，政府債務收益大幅下降。日本政府的十年期債券的收益率已經下跌到創紀錄的負0.135%，低於日本央行負0.1%的存款利率。隨著日本央行購買的政府債券年增長率接近80%，很難在否認這些政策不是債務貨比貨的一種形式。下面我們來解釋下原因。
獨立的中央銀行
任何自主發行貨幣的政府在理論上都可以無限制的發行鈔票。政府要麼收稅要麼借貸用於支出的觀點僅僅是我們建立的社會法律和基礎制度的一個結果。情形可能相反，但是何時印刷貨幣的決定權掌握在政客手中。
有人擔心過度的印刷貨幣和之後的消費將會導致通脹，之後通脹加劇最後導致放棄該貨幣。更進一步，假設經濟資源有限而政府無限制的印刷貨幣，那麼政府有可能控制所有這些資源，從而排擠所有的私營企業。顯然，一些人不會接受這一結果，而任何想要與政府在利用這些資源上的競争都會擡高價格。
為了解除這些恐懼，當代政府將貨幣發行的權利委托給獨立的中央銀行，希望能把政治因素和貨幣政策分開。如果央行的首要目標是維持價格穩定，政府就不能指望央行為他們的運作提供資金，所以必須以來稅收或者從個人手中借款。
債務貨幣化
個人持有政府債券意願的大小取決於債券相對其他投資的回報和風險。政府發行任何超過其稅收的債務將被認為是一個過度風險投資將會不得不支付更高的利率。因此，政府的財政政策受到市場的約束。
然而，央行有調整利率的權利。事實上，是他們在公開市場發佈的利率來維持價格穩定。央行通常發佈一個它認為能幫助實現通脹目標的利率，然手通過資產購買增加或者減少商業銀行短期政府債券的儲備以達到這個目標。
之後中央銀行通過在自由市場購買政府債券可以保證低利率，從某種程度上實現政府債務貨幣化。然而，這些日常公開市場操作不是那些強硬派進行債務貨幣化的想法。他們的想法是央行使用印刷貨幣的權利供應政府的巨大赤字開支，使政府債務達到一個如何和是否能被清償不確定的水平。這一舉動將會引起人們疑慮央行的獨立性在哪裡。
總結
政府債務水平超過GDP的230%，日本是世界上負債最嚴重的國家。隨著政府債券進入負收益率，政府在借貸中獲利。日本央行通過收取私人銀行的存款利息，日本央行實際上是在轉移財富，把控制經濟資源的能力從私人部門轉移到政府部門。這相當於通過減稅或者政府開支向經濟中扔錢。看起來很像債務貨幣化。
然而，雖然強硬貨幣政策態度持有者的態度令人擔憂，通脹實際上是日本央行的預期目標。由於通貨緊縮的壓力困擾著日本經濟。日本央行行長Kuroda表示：“重要的是日本央行堅定的致力於是想2%的通脹目標並將盡一起努力實現這一目標。”他仍然試圖維持日本央行的主要貨幣政策目標，碰巧日本政府是是唯一一個願意和有能力消費的經紀機構，因此創造總需求是一個非常迫切的需要。他只是不想把他的行為稱為“債務貨幣化”，希望人民仍然相信日本央行仍然具有至少是一部分的獨立性。
How Central Banks Monetize Government Debt
By Investopedia | March 25, 2016
With the Bank of Japan’s announcement on Jan. 29 to navigate into negative interest rate territory by charging interest on reserve deposits, yields on government debt have fallen precipitously. The yield on 10-year Japanese government bondsrecently fell to a record negative 0.135%, below the BOJ’s negative 0.1% reserve deposit rate. With the BOJ purchasing government bonds at an unprecedented annual rate of approximately 80 trillion yen, it is becoming exceedingly difficult for the BOJ governor, Haruhiko Kuroda, to deny that these policies are not a form of government debt monetization. We explain why below.
Independent Central Banks
Any government that issues its own currency (e.g. not Greece) could, in theory, continue to create money without limit. The idea that governments either have to tax or borrow in order to spend is really just a consequence of the legal and institutional infrastructure we, as a society, have created. Things could be otherwise, but when the monetary printing press is in the hands of politicians, the temptation to inflate currency is strong.
There is the fear that excessive printing of money and subsequent spending will lead to inflation, then hyperinflation, and then eventual abandonment of the currency. Further, assuming the limited nature of economic resources, if the government has unlimited amounts of money, then it could potentially control all of those resources, essentially “crowding out” the private sector. Obviously, this is problematic for some, and any attempt to compete with the government in utilizing resources leads to a bidding up of the price of those resources.
To mitigate these fears, modern governments have delegated the responsibility of money issuance to independent central banks, hoping to keep fiscal policy considerations separate from monetary policy ones. Since the primary goal of central banks is to maintain price stability (usually interpreted as low and stable inflation of around 2% a year), governments cannot depend on central banks to fund their operations and must either rely on tax revenue or, like everyone else, borrow money in private markets.
Debt Monetization
The willingness of the private sector to hold government debt will depend on the return and riskiness of that debt relative to alternative investments. Any government that issues debt far in excess of what it could collect in taxes is perceived as an excessively risky investment and will likely have to pay increasingly higher interest rates. Thus, a government’s fiscal policy has definite market constraints.
However, central banks have the power to manipulate interest rates. In fact, it is interest rates that they are targeting when they carry out their daily open market operations (OMO) to achieve price stability. The central bank typically states an interest rate target it believes will help it achieve its inflation target, and then increases or decreases the reserves of commercial banks through asset purchases – typically short-term government bonds – in order to achieve that target .
The central bank then, by purchasing government bonds in private markets can keep interest rates low, and in a sense, monetize government debt. However, these daily OMO are not what the more hawkish types have in mind when they talk about government debt monetization. What they have in mind is when central banks, by using their power to create money, accommodate massive deficit spending by the government, inflating the government’s debt to levels where it is not clear how or if it will ever be paid off. Such a move causes one to wonder how independent the central bank really is.
The Bottom Line
At a level of government debt that is more than 230% of its GDP, Japan is the most indebted nation in the world. With bond yields in negative territory, the government is now getting paid to borrow. By charging private banks interest on reserves held at the BOJ, Japan’s central bank is effectively transferring wealth, and thereby the ability to control the economy’s resources, from the private sector to the public sector. It amounts to a “helicopter drop” of new money that is channeled into the economy either through tax cuts or direct government spending. Sounds a lot like debt monetization.
Yet, while the potential for inflation is worrisome for the monetary hawks, inflation is actually Kuroda’s intended goal. With deflationary pressures plaguing the Japanese economy, Kuroda has stated, “What’s important is to show people that the BOJ is strongly committed to achieving 2 percent inflation and that it will do whatever it takes to achieve it.” He is still trying to maintain the BOJ’s primary monetary policy objective; it just so happens that the Japanese government is the only economic agent willing and able to spend, thus creating the aggregate demand that is so badly needed. He just doesn’t want to call what he is doing “debt monetization” in hopes that people will still believe that the BOJ maintains, at the very least, a modicum of independence.
本文翻譯由兄弟財經提供
文章來源：http://www.investopedia.com/articles/investing/032516/how-central-banks-monetize-government-debt.asp