What harm do minimum wages do? 最低工资有何危害?

2020年9月


Three decades of research have led to a major rethink
30年的研究带来了重大反思【“反思经济学基本理论”系列之二】 

 

What harm do minimum wages do? 最低工资有何危害?


FOR A LONG TIME economists—whose median income, according to a survey of the American Economic Association (AEA), is $104,000 a year—considered minimum wages to be harmful. A survey of AEA members in 1992 found that 79% of respondents agreed that a minimum wage increases unemployment among young and low-skilled workers. In an often fractious field, that is about as close to a consensus view as can be found. Although many economists recognised that low pay can indeed be a real problem, they argued that no pay was worse.
很长一段时间里,经济学家都认为最低工资是有害的(根据美国经济学会[American Economic Association,以下简称AEA]的调查,经济学家的年薪中位数为104,000美元)。1992年对AEA成员的调查发现,他们中有79%的人认同最低工资会增加年轻人和低技能工人的失业率。在经济学这个争吵不休的领域,这样的比例差不多等同于一致意见了。虽然许多经济学家承认工资太低确实可能引发切实问题,他们指出没有工资可拿就更糟糕了。
They were not the only people who thought so. The same argument was used by Republican politicians. In 1968, America’s federal minimum wage stood at its highest level since first being applied in 1938. During the following two decades it fell, in real terms, by 44%. Though Jimmy Carter raised the wage in each of the four years he was president, keeping pace with inflation, Richard Nixon raised it only twice in six years and Ronald Reagan not once in eight. Some state and local politicians, mostly Democrats, tried to offset the fall by raising their minimum wages, creating a patchwork of different levels. The disparities this created allowed detailed empirical research on the policies’ effects, and provided the means by which the economists’ consensus would be undermined.
并不是只有他们这么想。共和党政客也使用了同一套论证。1968年,美国联邦最低工资达到自1938年首次采用最低工资制以来的最高水平。随后20年里它的实值下跌了44%。尽管卡特在他任总统的四年里每年都提高最低工资以跟上通胀步伐,但尼克松在他的六年任期中只提高了两次,而里根的八年里一次都没有。一些州和地方的政客——大多是民主党人——试图通过提高本地的最低工资以补上跌去的部分,一幅参差不齐的图景由此产生。其中的差异使得人们可对最低工资政策的影响开展详尽的实证研究,为日后打破经济学家的共识提供了路径。
Not only did this see the conventional wisdom on minimum wages challenged in America; it also saw such policies spread elsewhere. Britain introduced a national minimum wage in 1998, and has increased it in recent years. Germany’s came into effect in 2015. Around 90% of countries have some sort of legal wage floor, although enforcement practices vary widely. Economists now have lots of data with which to understand how minimum wages affect the economy in practice and, in the context of a promise by Democratic presidential candidate, Joe Biden, to raise America’s federal minimum wage to $15, to argue about how high they can go.
这不仅让美国有关最低工资的传统观念受到了挑战,也使得这类政策传播到了其他地方。英国在1998年实施了全国最低工资,并在近年提高了标准。德国的最低工资制于2015年生效。大约90%的国家和地区都有某种法定的最低工资,尽管在执行上千差万别。现在,经济学家拥有了大量数据来了解最低工资在实践中如何影响经济,并且,在民主党总统候选人拜登承诺要把美国的联邦最低工资提高到15美元之际,争论最低工资可以被提高到多高。
The concern that minimum wages destroy jobs comes from the most basic of economic models: supply and demand. If labour is made more expensive, employers will probably want less of it. Textbooks state that, in the absence of a minimum wage, a worker is paid his “marginal product of labour”, which means the value of what he produces. There is no room to deviate from this wage in either direction. If an employer tries to pay a worker less, a rival firm will poach him. If the government imposes a minimum wage that is higher than a worker’s marginal product, the firm loses money by employing him. He is left jobless instead.
对最低工资损害就业的担忧源于最基本的经济模型:供求关系。如果把劳动力变得更昂贵,雇主很可能就会少要一点。按照教科书的说法,在没有最低工资的情况下,工人得到的是“劳动边际产量”,也就是他生产产品的价值。向上或向下都没有偏离这一工资水平的空间。如果雇主试图少付工资,那么竞争对手就会把人挖走。如果政府强制执行的最低工资高于一名工人的边际产量,那么公司就会因为雇用他而蒙受损失。这会让他反而丢了工作。
Reality is more complex. Firms do not know how much each worker contributes to their revenues. Few workers can find a new job at the drop of a hat. Yet the basic model reveals one important truth: the workers who are most vulnerable to losing their job as a result of the minimum wage are those whose productivity is low—the very people the policy is designed to help.
现实世界更加复杂。企业并不知道每个工人为自己的收益贡献了多少。没有哪个工人随随便便就能找到新工作。不过,这个基本模型仍然揭示了一个重要真相:最容易因为最低工资制度而丢了工作的是那些生产率低下的工人——恰恰是这项政策本来要帮助的人。
More sophisticated theorising about labour markets recognises that they are not perfectly competitive. There is no single wage at which a worker has his pick of employers. As a result, firms probably pay workers less than their marginal revenue product. How much less depends on negotiations and who does best there depends on bargaining power. In this framework, the goal of the minimum wage is not to defy market logic but to stop firms in a strong negotiating position from squeezing their workers.
关于劳动力市场的更复杂的理论指出它们并非完全竞争市场。并不存在哪个工资水平让一名工人可以随心所欲地挑选雇主。结果是,企业支付给工人的工资很可能少于其边际收益值。具体少多少则取决于谈判,而谁在谈判中争取到最好结果则取决于议价能力。在这种框架下,设定最低工资的目的不是要违背市场逻辑,而是要防止那些处于强势谈判地位的企业压榨工人。
The upper bound on the minimum wage still applies: firms will not willingly employ workers at a loss. But below that ceiling, the effect of the minimum wage is ambiguous. It depends on a series of questions. Can a company replace its workers with machines? Can it raise prices and make its customers pay for the minimum wage? Does it face competition from foreign firms who face laxer rules overseas?
最低工资的上限仍然适用:企业不会甘心亏本用人。但在这块天花板之下,最低工资的影响模糊不清。它取决于一系列问题。企业可以用机器代替工人吗?它能涨价来让顾客为最低工资买单吗?它是否面临来自外国公司的竞争,而这些外国公司在海外享受更宽松的规定?
Consider a comparison between factories and restaurants. Logically, there would be little scope to increase manufacturing pay using minimum wages, because firms face stiff international competition, and jobs are constantly automated away. By contrast, jobs in restaurants are hard to automate and face no foreign competition. Any increase in costs affecting the whole sector should be passed on to consumers. Job losses should be lower—especially if it turns out that consumers are willing to pay higher prices. So can one minimum wage do justice by both sectors?
来比较一下工厂和餐馆。从逻辑上讲,通过最低工资来提高制造业工资水平的空间极小,因为企业面临激烈的国际竞争,而且岗位在不断被自动化进程削减。相比之下,餐馆的工作很难自动化,也没有外国竞争的压力。任何影响整个行业的成本增加应该都会被转嫁给消费者。岗位流失应该会更少些——尤其是如果事实证明消费者愿意支付更高价格的话。那么同一个最低工资能在这两个行业都实现公正吗?
The empirical study which revitalised the debate on minimum wages in the 1990s was by David Card and Alan Krueger, both then at Princeton University. In 1992 New Jersey increased its hourly wage floor from $4.25 to $5.05. Neighbouring Pennsylvania kept its own at $4.25. Thrilled at the prospect of a naturally occurring case study, the two economists gathered information of employment at fast-food restaurants in both states before the April increase and again several months later. Fast food seemed to offer the ideal conditions for a study, as a homogenous sector employing unskilled workers.
让围绕最低工资的辩论重新活跃起来的那项实证研究是在1990年代由普林斯顿大学的戴维•卡德(David Card)和艾伦•克鲁格(Alan Krueger)开展的。1992年,新泽西州将最低时薪从4.25美元提高到了5.05美元,隔壁的宾夕法尼亚州继续维持4.25美元。眼看一个研究案例自然地出现了,两位经济学家兴奋不已。在当年4月这次薪资上调实施之前,两人收集了两个州内快餐店的用工情况,几个月之后再收集了一次。快餐业这个雇用非熟练工人的同质化部门似乎为研究提供了理想的条件。
The increase in the wage floor did not lead to jobs being lost in New Jersey; employment in the restaurants they looked at went up. Nor did the authors find any indication that the opening of future restaurants would be affected. Looking at the growth in the number of McDonald’s restaurants across America, they saw no tendency for fewer to open where minimum wages were higher.
最低工资的提高并没有导致新泽西州就业减少。在他们追踪的餐馆,受雇人数增加了。两位作者也没有发现任何显示未来新餐馆的开张会受影响的迹象。他们查看了麦当劳在美国各地增设分店的数字,没有发现在最低工资更高的地方新开门店更少的趋势。
Their book, “Myth and Measurement” (1995), changed a lot of minds. By 2000 only 46% of AEA members were certain that a minimum wage increased unemployment among the young and low-skilled: to the rest the textbook view—that, faced with a rise in the cost of employing workers, firms would use fewer of them—was wrong. But why? Over the past 20 years a growing body of research has shown that a key consideration is the power enjoyed by employers.
他们于1995年出版的著述《迷思与测量》(Myth and Measurement)改变了很多人的看法。到2000年,只有46%的AEA成员确信最低工资会增加年轻人和低技能工人的失业率。对于其余的人来说,教科书的观点——企业面对用工成本上升会减少雇人——是错的。但为什么错了?过去20年间,越来越多研究表明,一个关键的考量因素是雇主享有的权力。
This school of thought argues that some labour markets are characterised by a market structure known as monopsony. Under a monopolistic regime one dominant supplier sells to many buyers, whereas under a monopsonic regime, one dominant buyer purchases from many sellers. Just as a monopolist can set prices higher than would be the case in a competitive market, a monopsonist can set prices artificially lower.
这个思想学派认为,某些劳动力市场的特征是被称为买方垄断的市场结构。在卖方垄断系统中,一个强势的供应商向众多买家出售货品,而在买方垄断系统中,一个强势的买家从许多卖家那里购买货品。正如垄断的卖方可以设定高于竞争市场售价的价格,垄断的买方可以人为拉低价格。 
Thus, though it may sound counterintuitive for a higher wage to lead to more employment, it makes sense if what the legislation is doing is pushing a wage kept artificially low by monopsony back to where it would be in a market where supply and demand were matching each other freely. People who may not have bothered to look for a job at $10 an hour may be drawn into a job market offering $15 an hour. Push the minimum wage significantly beyond that point, though, and jobs will indeed be lost as companies find labour too expensive to afford.
因此,尽管“提高工资会增加就业”听上去可能有违直觉,但如果相关立法是把被垄断的买方人为压低的工资推回到在一个供求自由匹配的市场中应有的水平,那么它就讲得通了。那些本来可能懒得找一份10美元时薪工作的人可能会被15美元时薪重新吸引回就业市场。但是,如果把最低工资提高到大大超过这个节点,那么就真的会发生岗位流失,因为企业负担不起劳动力了。
Once the role of competition in the labour market is accepted, the debate on minimum wages becomes more nuanced and more empirical. Gathering data is not easy. Researchers must consider whether to track jobs or workers, and whether to study certain groups, such as teenagers or the unskilled, or broader sectors. And the job market is affected by more than just minimum-wage rules. Constructing reasonable counterfactuals is hard.
一旦人们接受了竞争在劳动力市场中的作用,关于最低工资的辩论就变得更加细致也更基于实证。收集数据并不容易。研究人员必须斟酌是去追踪岗位还是工人,是研究某些特定群体——比如青少年或非熟练工人——还是更广泛的行业和部门。而就业市场不仅仅受到最低工资规定的影响,要构建合理的反事实情境很难。
Specific north-west 独特西北区 Consider an example from Seattle. The city has been at the forefront of the “fight for $15” campaign that led to Mr Biden’s pledge, and its rapid wage rises have made it an attractive laboratory for economic studies, despite the fact, some grumble, that it is unrepresentative. A paper by Ekaterina Jardim and others at the University of Washington, published in 2017, found that minimum-wage increases in the city in 2015 and 2016 led to employers reducing hours in low-paid sectors. The average low-paid worker earned more per hour but, because they worked fewer hours, their monthly earnings dropped by $74—the equivalent of five hours’ pay.
来看看西雅图的例子。这座城市在“为15美元而战”运动(拜登的承诺由此而来)中一直走在最前沿,这里工资的快速上涨使它成为一个颇有吸引力的经济研究实验室,尽管一些人抱怨它缺乏代表性。华盛顿大学的叶卡捷琳娜•雅尔丁(Ekaterina Jardim)等人在2017年发表的一篇论文发现,2015年和2016年该市最低工资的上涨导致雇主缩短了低薪部门的工作时长。一名典型低薪工人的时薪更高了,但因为工时减少,他们的月收入下降了74美元——相当于五小时工资。
That paper used aggregate data on hours and earnings by sectors. In a paper published in 2018, the same authors used administrative data to track individual workers rather than looking at averages. This time they found that low-paid workers saw their weekly earnings increase by $8-12 a week. The majority of that gain, though, was taken by low earners with above-median experience levels and some of it from workers making up lost hours worked in Seattle with additional hours elsewhere in Washington state.
那篇论文使用了各行各业的工时和收入的汇总数据。在2018年发表的另一篇论文中,同一批作者用行政管理数据来追踪工人个体,而非查看平均值。这次,他们发现低薪工人的周收入增加了8到12美元。不过,这一增长的大头被经验水平在中位数以上的低收入者拿走了,其中有一部分是从在西雅图工作时长减少的工人那里转移而来,后者靠在华盛顿州的其他地方增加工时来弥补损失。
In 2019 a review commissioned by the British government of more than 50 recent empirical studies into wage floors found the effect on employment to be generally muted, even with relatively ambitious increases. Yet some studies did find higher impacts. Arindrajit Dube, the author of the review, warned that the evidence base is still developing. It is, for instance, too soon to opine on South Korea’s 25% increase in its minimum wage between 2016 and 2018.
英国政府在2019年委托撰写的一份综述回顾了近年有关最低工资的50多项实证研究,结果发现它们对就业的影响总体上很微弱,即便提升幅度较大时也一样。不过,其中有些研究确实发现了更大的影响。这份综述报告的作者阿林德拉吉特•杜贝(Arindrajit Dube)警告说,证据基础仍在发展中。比如,对于韩国在2016年至2018年间将最低工资提高了25%的影响,要发表意见还为时过早。
The effects of a wage floor can also be felt outside low-pay sectors. A preliminary study in 2019 of the impact of Germany’s minimum wage found it led to more reallocation of workers from smaller, lower-paying firms to larger, higher-paying ones. The same year an article in the Quarterly Journal of Economics found that the impact of minimum-wage laws on average earnings was amplified by small but important spillover effects higher up the earnings ladder. Employers tend to want to maintain some sort of wage differential for staff with more responsibility. So if the minimum wage boosts the pay of fast-food workers, then restaurants may also need to raise the pay of fast-food supervisors.
在低薪工种之外也能感受到最低工资的影响。2019年对德国最低工资制度影响的一项初步研究发现,它导致更多工人从较小的、薪资更低的公司转移到较大的、薪资较高的公司。同年发表于《经济学季刊》(Quarterly Journal of Economics)的一篇文章发现,最低工资立法在收入阶梯的更高处产生了虽小却重要的溢出效应,扩大了这类法律对平均收入的影响。雇主倾向于为那些肩负更多责任的员工维持某种工资差异。因此,如果最低工资提高了快餐工人的工资,那么餐馆可能也需要提高快餐主管的工资。
Who pays for the minimum wage? In theory a higher cost base could be passed on to consumers through higher prices, or absorbed by employers through lower profit margins. In reality the answer varies by market. In competitive sectors, such as fast food, research has found that a 10% increase in the wage floor pushes up burger prices by just 0.9%. In 2019 a study of supermarkets in Seattle found no impact on grocery prices from big increases.
谁为最低工资买单?从理论上讲,更高的成本基数可以通过更高的产品价格转嫁给消费者,或通过更低的利润率由雇主吸收。在现实中,答案因市场而异。在快餐业等竞争性行业中,研究发现最低工资提高10%仅仅使汉堡价格上涨了0.9%。2019年对西雅图超市的调查没有发现最低工资大幅上涨影响食品杂货价格。
Economists no longer think higher minimum wages are always bad. But that is not the same as saying they are always good. In 2018 a paper by Isaac Sorkin and others cautioned policymakers to take a longer-term view, rather than worry about short-term unemployment. Its authors found that if firms perceived a higher wage floor to be permanent and unlikely to be eroded by inflation, it could encourage them to automate more and decrease employment growth in the future. The idea that a minimum wage can sometimes lead to higher rather than lower employment does not mean it always will. When pushing up the floor, policymakers need to ensure they do not hit the ceiling.
经济学家不再认为提高最低工资总是不好的。但这并不等同于说它们永远是好的。艾萨克•索尔金(Isaac Sorkin)等人在2018年发表的一篇论文告诫政策制定者,相比担心短期失业率,他们需要看得更远些。作者发现,如果企业认为更高的最低工资会永久持续却不大可能被通胀抵销,那么这可能会促使它们扩大自动化而缩减劳动力增长。最低工资有时会增加而非减少就业,但并不意味着永远如此。在抬高这块地板时,政策制定者需要确保自己不会触到天花板。