What happens when the Fed starts losing money

EVER since the Federal Reserve first started buying up financial assets back in 2008, some have fretted about taxpayer exposure. The private debt purchased by the Fed to prop up the financial system might sour. The government bonds it has bought with newly created money, a strategy dubbed “quantitative easing” (QE), could fall in value if interest rates rose.

自美联储2008年首次开始购买金融资产以来，一些人深为纳税人的风险苦恼。美联储为提振金融体系而进行的私营债务购买可能发酵，如果利率上升，那么其通过印钞来购买的政府债券——即“量化宽松(QE)”——资产可能缩水。 

The reality has been happier. The Fed’s assets have ballooned to nearly $3 trillion, mostly in Treasuries and mortgage-backed securities (MBS). It paid $89 billion in profit to the Treasury for 2012, the largest in a string of record-breaking remittances (see chart). Before the crisis, the Fed’s profits were typically only a third of that.

现实倒是更为乐观，美联储资产已经升至近3万亿，大部分是国债和抵押贷款支持证券(MBS)，他们在2012年向美国财政部支付了890亿美元的利润，从图表可见，这是破历史纪录的数据，危机前美联储的利润仅为该水平的1/3。 

The Fed makes its money much as most banks do: from the spread between the return on its assets and the interest paid on its liabilities. The Fed’s liabilities are principally made up of currency in circulation, which pays no interest, and reserves, the cash that commercial banks keep on deposit at the Fed. Since 2008 these reserves have exploded to $1.6 trillion, on which the central bank pays only 0.25% interest. The difference between that modest cost and the average return of about 3.5% on its bond holdings explains the whopping “seigniorage”, as the profit the Fed earns from printing money is called.

美联储从资产回报和债务利率支付间获得收益，这和大部分银行一样。美联储的债务主要由流通的货币(这不用支付任何利息)和商业银行存在美联储处的存款组成。自2008年以来，这些存款已经达到1.6万亿美元，而美联储只支付0.25%的利息。可忽略不计的成本和约3.5%的平均债券持有回报之间的差距解释了美联储巨大的“铸币特权”，也就是美联储通过印钞获得的利润。 

Some Fed officials worry about what comes next. When the Fed raised rates in the past, it meant little for profits because reserves were trivial and earned no interest. Since 2008 the Fed has paid interest on reserves in order to maintain control of interest rates. So when the Fed eventually tightens monetary policy, it will have to pay out more interest. To absorb reserves it may have to sell some bonds for less than what it paid, incurring capital losses. In theory, it could end up losing money, a risk that grows the more bonds it buys.

部分美联储官员担忧的是接下来的事情：当美联储升息，这意味着随着存款减少，利息没有导致的利润变少。自2008年以来美联储为了维持对利率的控制，已经向存款支付利率。因此当美联储最终收紧货币政策，其不得不支付更多利息。为了吸收存款他们不得不抛售部分债券来减少支付的资金，这将招致资本损失。理论而言美联储最终会亏损，该风险随着购买债券的量而递增。

In a recent paper five Fed economists calculated that if the Fed buys $1 trillion of bonds this year and starts tightening in 2014, then the Fed’s profit will turn to loss by 2017. Cumulative losses could eventually reach $40 billion, from higher interest expenses and realised losses on MBS sales (the economists assume the Fed will hold its Treasuries to maturity). If interest rates rise more sharply than expected, losses could peak at $125 billion, and the Fed would pay no profit for six years.

在近期的文献中，5位美联储经济学家计算，如果美联储今年购买1万亿美元的债券，并在2014年收紧货币政策，那么美联储将在2017年出现扭赢为亏的局面。从走高的利率支付和销售MBS的实际损失累计的损失最终可能达到400亿美元，而经济学家认为美联储会将国债持有至到期。如果利率超预期上升，损失可能达到1250亿美元的高峰，那么美联储可能6年难以获利。 

For the government as a whole, these losses are less than meets the eye. The interest paid on reserves by the Fed partly substitutes for interest the Treasury would be paying the public if its bonds were not held by the central bank. But it may still worry some Fed officials, given the attacks it regularly endures from Republicans in Congress. “Being seen to have lost taxpayer money could only intensify pressures on the Fed, to the point where at least some of the central bank’s independence could be put at risk,” says Roberto Perli, a former Fed economist now with ISI Group, a broker. He thinks some officials could be worried enough to oppose continuing QE once it reaches $1 trillion at the end of this year, even if the economy is not yet up to snuff.

对政府整体而言，这些损失比眼前的要小。美联储为存款支付的利息，部分代替了财政部向公众支付的利息(如果债券持有人不是央行的话)。但鉴于来自国会共和党人的供给，这同样令一些美联储官员担心。前美联储经济学家、ISI Group交易员Roberto Perli表示，被发现纳税人的钱蒙受损失只会加剧美联储身上的压力，在某种程度上而言至少央行独立性可能存在被诟病的风险。他认为部分官员的担忧足以令其在今年年底宽松量达到1万亿后，反对继续实行QE，哪怕经济状况还不足够良好。 

Whether such concerns would really blow the Fed off the course dictated by economic circumstances is debatable, however. The Fed would not actually need a taxpayer infusion. One of the perks of central banking is that it can print the money needed to pay interest. If that generates a loss, it creates an offsetting “deferred asset” on its balance-sheet, representing future profits it won’t have to send to the Treasury. The forgone profit would pale in comparison with total interest saved, higher tax revenue due to stronger growth and roughly $500 billion of profit that QE had previously made possible. More importantly, the losses would occur only once the economy was healthy enough to require higher interest rates, which, after all, would be proof that QE had worked.

不过无论类似的担忧会否撼动美联储的计划，美联储都不会真的需要纳税人的支付。央行的特权之一是可以通过印钞来支付利率。如果产生损失，央行可以抵消资产负债表上延递资产，这代表不用递交给财政部的未来利润。预先知晓的利润和省下来的总利息、强劲增长获得的高税收、以及此前实施QE生成的约5000亿美元利润比较，则相形黯淡。更为重要的是，只有经济足够健康，需要升息时才会产生损失，而这反而证明QE产生效果了。