債務增肥--政府能借的錢多到超乎以往所能想像

 Putting on weight 債務增肥

Governments can borrow more than was once believed 

政府能借的錢多到超乎以往所能想像

Hence only muted concern about borrowing to respond to covid-19

因此對舉債抗疫顧慮輕微

Schools brief

Sep 12th 2020 edition

Sep 12th 2020

If people know one thing about the thinking of John Maynard Keynes, who more or less founded macroeconomics, it is that he was in favour of governments borrowing lots of money, at least under some circumstances. The “New Keynesian” orthodoxy that evolved from his work in the second half of the 20th century was much less liberal in this regard. It put less faith in borrowing’s purported benefits, and had greater concerns about its dangers.

凱因斯（John Maynard Keynes）或多或少創立了總體經濟學，他的思想若有一點廣為人知，那就是贊同政府借入大量資金，至少在某些情況下這麼做。到20世紀下半葉，從他研究演變而來的「新凱因斯主義」正統觀念，對這方面的寬容大不如前----對舉債聲稱的益處信心薄弱，卻更加擔憂其危險性。

The 2010s saw the pendulum swinging back. In large part because they feel bereft of other options, many governments have borrowed heavily—and as yet they have paid no dreadful price. Can this go on?

在2010年代，鐘擺又擺回來。許多政府大量舉債，主要因為他們覺得別無選擇。目前為止尚未付出沉重的代價，但這種情況能持續下去嗎？

Keynes’s ideas about borrowing reflected his view of recessions—and in particular, the Depression of the 1930s, during which he wrote “The General Theory of Employment, Interest and Money”—as vicious circles. Recessions come about when the economy is hit by a sudden rise in the desire to save money; such desires lead to lower spending, which leads to more unemployment, which leads to yet less spending, and so on. If the government borrows enough to offset lower private spending with increased spending of its own the circle can be broken—or stopped from getting going.

凱因斯對舉債的觀念反映他對經濟衰退的看法--有如惡性循環。尤其是1930年代的大蕭條，他在那段時期寫下《就業、利息和貨幣的一般理論》。大蕭條來臨時，經濟遭突然暴增的儲蓄需求打擊；儲蓄欲望導致支出降低，進而導致更多人失業，而這又導致支出減少，如此循環下去。如果政府舉債來增加公共支出，足以抵消減少的民間支出，那麼這個迴圈就可以被打破，停止繼續循環下去。

Most early Keynesians assumed that the deficits caused by borrowing to stimulate the economy would be temporary; after borrowing more than they raised in taxes in order to provide a fiscal stimulus, governments would be able to raise more in taxes, and thus pay off their debts, in the good times that followed. Some, though, suspected that the structure of the advanced economies of the 1930s might mean they were low on demand even in the good times, and that a permanent deficit might be necessary to keep the economy going at a rate that minimised unemployment.

早期凱恩斯主義者大多假設，因舉債刺激經濟造成的赤字是暫時的；政府借入超過稅收的額度提供財政刺激，將能在隨後的繁榮時期徵得更多的稅，進而償還債務。不過，有些人懷疑，從1930年代先進經濟體的結構來看，或許意味著需求低迷，即使在繁榮時期也一樣，而常態性的赤字可能是必須的，好讓經濟成長維持在使失業率最小化的速度。

Debates about the proper role of fiscal stimulus became less urgent in the decades after the second world war, as robust economic growth eased worries that demobilisation might bring a return of Depression-like conditions. Faith in Keynesian orthodoxy was further shaken by the economic developments of the 1970s and 1980s. Some economists began to argue that the public would eventually adjust to stimulus measures in ways that weakened their impact. Robert Barro, a leading proponent of this “rational expectations” approach, argued that a fiscal stimulus paid for by borrowing would see households spend less and save more, because they would know that tax rises were coming. This decreased private spending would then offset the increased public spending.

在二次世界大戰後幾十年，有關財政刺激適當角色的辯論，變得不太急迫。因為強勁的經濟成長，緩和了解除動員可能回到大蕭條情況的擔憂。1970到1980年代的經濟發展，進一步動搖對正統凱因斯主義的信仰。一些經濟學家開始認為，民眾對刺激措施的調適行為，終將削弱政策的影響。這種「理性預期」方法的主要倡議者巴羅（Robert Barro）主張，舉債支付的財政刺激措施將使家庭支出減少、儲蓄變多，因為他們知道增稅將至。減少的私人消費將抵消增加的公共支出。

Linked to, but broader than, such academic questions was the fact that, by the 1970s, the ways in which Keynesian governments had been running their economies seemed to have failed. A trifecta of slowing growth, soaring inflation and high unemployment brought the idea of governments being able to avoid recessions through stimulus into disrepute.

與這種學術問題有關、但涵蓋面更廣的事實是，到了1970年代，奉行凱因斯主義的政府管理經濟的方式似已失敗。成長放緩、通膨竄升和高失業率三重打擊，使政府能藉由刺激避免衰退的想法，公信力蕩然無存。

The new orthodoxy was that governments should instead rely on monetary policy. When the economy slowed, monetary policy would loosen, making it cheaper to borrow, thus encouraging people to spend. Government borrowing, for its part, should be kept on a short leash. If governments pushed up their debt-to-GDP ratio, markets would become unwilling to lend to them, forcing up interest rates willy-nilly. The usefulness of monetary policy demanded a sober approach to fiscal policy.

新的正統觀念是，政府應改為依賴貨幣政策。經濟放緩時，貨幣政策將寬鬆，使借貸成本降低，進而鼓勵人們消費。另一方面，政府舉債應被緊緊束縛。如果政府提高債務對GDP的比率，市場將不願意借錢給政府，迫使利率不得不提高。貨幣政策要奏效，需要搭配一套嚴謹的財政政策做法。

The 2000s, however, saw a problem with this approach beginning to become plain. From the 1980s, interest rates had been in a long, steady decline. By the 2000s they had reached historical lows. Low rates made it harder for central banks to stimulate economies by cutting them further: there was not room to do so. The global financial crisis pushed rates around the world to near zero.

但在2000年代，這種做法的問題開始變得顯而易見。從1980年代開始，利率一直長期穩定下降。到2000年代，利率降到歷史低點。低利率使央行難以進一步降息來刺激經濟：沒有再降的餘地了。全球金融危機已將各國利率壓到接近零。

Governments experimented with more radical monetary policy, such as the form of money printing known as “quantitative easing”. Their economies continued to underperform. There seemed to be room for new thinking, and a revamped Keynesianism sought to provide it. In 2012 Larry Summers, a former American treasury secretary, and Brad DeLong, an economist, suggested a large Keynesian stimulus based on borrowing. Thanks to low interest rates, the gains it would provide by boosting the growth rate of GDP might outstrip the cost of financing the debt taken on.

各國政府嘗試更激進的貨幣政策，像是被稱為「量化寬鬆」的印鈔模式，但經濟仍毫無起色。此時似乎有新思維的空間，改良版的凱恩斯主義乘隙而入。 2012年前美國財政部長薩默斯（Larry Summers）和經濟學家德隆（Brad DeLong）建議在舉債的基礎上，實施大規模的凱因斯式刺激措施。由於利率正低，透過提高GDP成長率將帶來的收益，可能超過債務的融資成本。

In the following year Mr Summers followed some 1930s Keynesians, notably Alvin Hansen, in suggesting that borrowing in order to stimulate might be needed not just as an occasional pick-me-up, but as a permanent part of the economy. Hansen had argued that an ageing population and a low rate of technological innovation produced a long-term lack of demand which he called “secular stagnation”. Mr Summers took an updated but similar view. Part of his backing for this idea was that the long-term decline of interest rates showed a persistent lack of demand.

次年，薩默斯與1930年代的凱因斯主義者，特別是漢森（Alvin Hansen），提出舉債刺激經濟可能是需要的，這不僅只是短暫的興奮劑，而且是經濟永久的一部分。漢森主張，人口老化和技術創新率低導致長期需求不足，他稱之為「長期停滯」。薩默斯發表更新但相似的觀點。他支持這想法的部分原因是利率長期下降，顯示需求持續匱乏。

Way down we go 一路走下去

Sceptics insisted that such borrowing would drive interest rates up. But as the years went by and interest rates remained stubbornly low, the notion of borrowing for fiscal stimulus started to seem more tenable, even attractive. Very low interest rates mean that economies can grow faster than debt repayments do. Negative interest rates, which have been seen in some countries over recent years, mean that the amount to repay will actually be less than the amount borrowed.

懷疑者堅稱舉債會推升利率。但是，多年過後，利率依舊低迷，舉債推行財政刺激的觀念開始顯得更站得住腳，甚至更具吸引力。極低的利率意味著經濟成長可以比償債速度更快。近年來在一些國家已看到負利率，這意味著償還的金額實際上將少於借入的金額。

Adherents of “Modern Monetary Theory” (MMT) went further than this, arguing that governments should borrow as much as was needed to achieve full employment while central banks focused simply on keeping interest rates low—a course of action which orthodox economics would expect to promptly drive up inflation. Currently MMT remains on the fringes of academic economics. But it has been embraced by some left-wing politicians; Senator Bernie Sanders, the candidate beaten by Joe Biden for the Democratic nomination, counted an MMT enthusiast, Stephanie Kelton of Stony Brook University, among his chief advisers.

現代貨幣理論（MMT）的擁護者進一步主張，各國政府應為實現充分就業，盡可能地借錢，而央行只要專注於維持低利率----這種行動路線，按傳統經濟學來看，勢必會迅速推升通膨。當前，MMT仍處於經濟學界的邊緣，但已獲一些左翼政治人物［叮嚀：除非明顯有貶抑意思才譯「政客」］敞臂接納。與拜登爭民主黨提名落敗的參議員桑德斯（Bernie Sanders），他的主要顧問就包括一位MMT狂熱者--石溪大學的科爾頓（Stephanie Kelton）。

The shift in mainstream thinking on debt helps explain why the huge amounts of government borrowing with which the world has responded to the pandemic has not worried economists. But now that governments have, if only for want of an alternative, become more willing to take on debt, what should be their limit? For an empirical answer, it is tempting to consider Japan, where the ratio of net public debt to GDP stood at 154% prior to the pandemic.

有關債務的主流思想轉變，有助於解釋為什麼世界各國政府大量舉債抗疫，經濟學家卻不憂心。但既然政府已變得更願意承擔債務，即使只因別無選擇，那麼舉債極限應該在哪？要找個實證的答案，不由得令人想到疫情爆發前的日本：公債淨額對GDP的比率為154％。

If Japan can continue to borrow with that level of debt, it might seem that countries with lower levels should also be fine. But this ignores the fact that if interest rates stagger back from the floor, burdens a lot smaller than Japan’s might become perilously unstable. There is no immediate account for why this might be likely. But that does not mean it will not happen. And governments need to remember that debt taken on at one interest rate may, if market sentiment changes, need to be rolled over at a much higher one in times to come.

如果日本可以繼續以這樣的水平舉債，那麼債務水平較低的國家似乎也應該沒事。但這忽略了一個事實，如果利率從谷底踉蹌回升，就連遠比日本小的債務負擔，都可能變得岌岌可危。雖沒立即說明為何這可能發生，並不表示就不會發生。政府還需記住，如果市場風向改變，以某個利率發行債券的債務，可能必須在日後以更高的利率展延。

Given this background risk, governments ideally ought to make sure that new borrowing is doing things that will provide a lasting good, greater than the final cost of the borrowing. If money is very cheap and likely to remain so, this will look like a fairly low bar. But there are opportunity costs to consider. If private borrowing has a high return and public borrowing crowds it out, then the public borrowing either needs to show a similarly high return or it needs to be cut back.

考慮此背景風險，理想上，政府應確保新借入的資金，要花在未來能提供源源不絕收益的計畫上，而這些收益須超過最終借貸成本。若資金非常便宜且可能持續下去，這看起來是相當低的要求。但還有機會成本要考慮。如果借錢給私部門的回報率高，卻遭到借給公部門的額度排擠掉，那麼公部門借貸必須拿出同樣高的報酬率，不然就得少借一些。

At the moment private returns remain well above the cost of new borrowing in most places: in America, for instance, the earnings of corporations are generally high relative to the replacement cost of their capital. This makes it conceivable that resources used by the government would generate a greater level of welfare if they were instead mobilised by private firms.

目前，大多數地方私部門的報酬率仍遠高於新借貸的成本：例如，美國企業的收益通常高於資產的重置成本。可想而知，如果政府使用的資源改由私營公司運用，會創造出更多福祉。

But it does not currently look as though they would be. Despite the seemingly high returns to new capital, private investment in America is quite low. This suggests either that there are other obstacles to new investment, or that the high returns on investment reflect an insufficient level of competition rather than highly productive companies.

但目前看來事與願違，儘管新資本似乎可獲高額報酬，美國的私營部門投資仍然很低。這顯示可能存在其他新投資障礙，不然就是高投資報酬率反映的不是公司生產力高，而是市場競爭不足。

Both possibilities call for government remedy: either action aimed at identifying and dismantling the obstacles to investment, or at increasing competition. And until such actions produce greater investment or lower returns, the case for government borrowing remains quite strong. This is even more the case for public investments which might in themselves encourage the private sector to match them—“crowding in”, as opposed to crowding out. Investment in a much better electricity grid, for example, could increase investment in zero-carbon generation.

這兩種可能性都需要政府採取補救行動：查明並消除投資障礙，或促進市場競爭。在這些行動促進更多的投資或降低報酬率之前，政府舉債的理由仍很充分。公部門投資的理由甚至更充足，可能還會鼓勵私營部門比照辦理----「擠進」投資而不是排擠。例如，投資建設更好的電網，可能助長對零碳發電的投資。

In the long run, the way to avoid having to borrow to the hilt is to implement structural changes which will revive what does seem to be chronically weak demand. Unfortunately, there is no consensus over why demand is weak. Is technological progress, outside the realm of computers and communications, not what it was? Is inequality putting money into the hands of the rich, who are less likely to spend their next dollar, rather than the poor, who are more likely? Are volatile financial markets encouraging precautionary saving both by firms and governments? Is the ageing of the population at the root of it all?

從長遠來看，避免深陷債務的方法是實施結構性改革，這將提振似乎長期疲軟的需求。不幸的是，對於為何需求疲軟尚無共識。難道電腦和通訊領域外的技術進步大不如前？難道貧富不均使錢落入富人手中後，他們比窮人更不可能花下一美元，而窮人更可能花用？波動的金融市場促使企業和政府儲蓄，以備不時之需？人口老化是這一切的根源嗎？

Making people younger is not a viable policy option. But the volatility of markets might be addressed by regulation, and a lack of competition by antitrust actions. If inequality is at the root, redistribution (or its jargony cousin, predistribution) could perk up demand. Dealing with the structural problems constraining demand would probably push up interest rates, creating difficulties for those governments which have already accumulated large debt piles. But stronger underlying growth would subsequently reduce the need for further government borrowing, raise GDP and boost tax revenues. In principle that would make it easier for governments in such situations to pay down their increased debt.

使人民變年輕不是可行的政策選項，但市場波動可藉由監管解決，缺少競爭也可透過反壟斷行動解決。若不平等是根源，重新分配（另一近似術語是「預先分配」）可能會激起需求。處理造成需求受限的結構性問題，也許會推高利率，給已經債台高築的政府製造麻煩。但強勁的成長基礎將減少政府日後進一步舉債的需求、提高GDP並增強稅收。原則上，在此情況下，政府可以更輕鬆地償還增加的債務。

The new consensus that government borrowing and spending is indeed an important part of stabilising an economy, and that interest rates are generally low enough to allow governments to manage this task at minimal cost, represents progress. Government borrowing is badly needed to deal with many of the world’s current woes. But this consensus should ideally include two additional planks: that the quality of deficit-spending still matters, and that governments should prepare for the possibility of an eventual change in the global interest-rate environment—much as 2020 has shown that you should prepare for any low-probability disaster. ■

新的共識是：政府的借貸和支出確實是穩定經濟的重要部分，且利率普遍較低，足以使政府以極低的成本達成這項任務。這代表進步。政府借錢對處理當今世上的許多困難是亟需的。但是，理想情況下，這種共識還應包括兩個額外的條款：赤字支出的品質仍然重要，且政府應為全球利率環境終將改變的可能性做準備--就像2020年的啟示，你得為任何罕見的災難未雨綢繆。 ■