Pamela Gordon sighs as she recalls how her parents came to Chicago in the 1950s from Mississippi, following the “Great Migration” of African-Americans to the industrial Midwest.

　　在追忆自己父母在上世纪50年代是如何从密西西比州迁到芝加哥时，帕梅拉·戈登(Pamela Gordon)叹了口气。在那场“大迁徙”中，大量非裔美国人迁移到美国中西部的工业地区。

　　“They were at the median, but coming from the south, they considered they were doing well,” she says. “My father worked at the National Can factory and my mother was a beautician. They had enough money to pay the mortgage, to afford a Cadillac, and they took us out once a week to eat and to go to the movies. They felt very middle class.”

　　“当时他们属于中等收入家庭，但由于是在南方，他们自认为生活得不错，”她说道。“我父亲在国家罐头厂(National Can)工作，母亲是个美容师。他们的薪水足够支付房贷和供一辆卡迪拉克(Cadillac)，每周还能带全家出去吃一顿饭，看场电影。他们觉得自己是正宗的中产阶级。”

　　Like her parents, Ms Gordon, 55, is at the median. Between her job as an administrative assistant at a dentist’s office in Rockford, a city of 150,000 some 90 miles north-west of Chicago, and her husband’s work at a call-centre, they make $52,000 a year – close to the annual median household income of about $50,000, according to the Census Bureau.

　　与其父母一样，现年55岁的戈登女士也是中等收入。她在罗克福德(Rockford)市——该市位于芝加哥西北约90英里，人口约15万——一家牙医诊所里做行政助理，丈夫在一家客户服务中心工作，家庭年收入5.2万美元，接近美国人口统计局(Census Bureau)公布的约5万美元的美国家庭年均收入。

　　Asked if she considers herself middle class, however, Ms Gordon shakes her head. “I think middle class would be someone who doesn’t have to wait for payday to pay bills,” she says. “If I miss a pay check, I’m in trouble. Middle-class people could miss a few and they’d be fine. They have savings.”

　　但在被问到是否觉得自己是中产阶级时，戈登摇了摇头。“就我理解，中产阶级不必指望薪水来支付账单，”她说道。“如果有一个月没有收入，我就有麻烦了。中产阶级撑几个月也不会有问题。他们有存款。”

　　Her story encapsulates what has happened at the midpoint of US household incomes, where wages have stagnated since the late 1970s and declined since the turn of the century. Both the relative quantity and quality of US median-income jobs has deteriorated, from postwar manufacturing jobs to the rise of low-paying employment in industries such as retail.

　　她的故事是美国中等收入家庭的缩影。自上世纪70年代末以来，这部分家庭的收入水平一直处于停滞状态，进入21世纪后，甚至有所下降。从战后的制造业工作到零售业等低收入行业工作的增多，美国中等收入工作的相对数量和质量都有所下降。

　　Coupled with recession effects, that long-term secular decline has undermined the American dream. The housing crisis has left millions owing more than their homes are worth, while the distance between top earners and the median has grown, and the number of well-paying factory jobs has shrunk. Such factors imperil a recovery, reliant on the buying power of ordinary Americans.

　　收入长期持续下降，加上经济衰退的影响，已经给美国梦蒙上了阴影。住房危机导致数百万家庭的负债额超过了房产价值，而高收入与中等收入家庭之间的差距也有所加大，高待遇工厂的岗位数量也有所缩减。这些因素威胁到了依赖普通美国人购买力的经济复苏。

　　“The home ownership aspect of the American dream has turned into a nightmare, while the idea that anyone can make it, or that your children will do better, seems an illusion for many Americans,” says Robert Reich, the former US labour secretary, now a professor at the University of California at Berkeley.

　　前美国劳工部长、现任加州大学伯克利分校(University of California at Berkeley)教授罗伯特?赖克(Robert Reich)表示：“美国梦中拥有住房这部分已变成了梦魇，而任何人都能实现美国梦、或你的子女会更成功的观念，对于许多美国人而言似乎都是一种错觉。”

　　Ms Gordon says her essential monthly expenses leave her with almost no disposable income. She bought her home in 2007, the height of the market, and it is almost certainly worth less than the $103,000 she owes on it. Her monthly mortgage payment, including property taxes, is $1,100. The interest rate is 7 per cent and she has been unable to refinance at a lower rate. Other expenses include a $500-a-month car loan, which she needs for driving to work, $600 in petrol and grocery bills.

　　戈登表示，每月的基本支出让她几乎没有任何可支配收入。她是在2007年市场位于高点时买的房，目前房子价值几乎肯定低于她欠的房贷——10.3万美元。她每月还贷（包括房产税）1100美元。贷款利率为7%，而她一直无法以更低的利率进行再融资。其它支出包括每月500美元的汽车贷款——她上班需要开车——以及600美元的汽油和食品费用。

　　Rockford, a former manufacturing city that used to have incomes far above the national average, is full of such stories. Kishwaukee Street, a main thoroughfare, is dotted with abandoned buildings that were once factories, petrol stations, car showrooms and bars.

　　在罗克福德，类似的家庭比比皆是。这里以前是一个制造业城市，收入远高于全国平均水平。在主干道Kishwaukee大街上，随处可见以前的工厂、加油站、汽车展厅和酒吧等废弃建筑物。

　　Larry Morrissey, the mayor, says manufacturing jobs, once plentiful, are now aspirational. “The people in the middle would like to be in those jobs but they’re working in the service sector, at places like Walmart,” he says. “This is an overlooked and under-represented class.”

　　该市市长拉里·莫里西(Larry Morrissey)表示，以前充足的制造业工作机会眼下都成了奢望。“中等收入的人愿意从事这些工作，但现在他们都在服务业、例如沃尔玛(Walmart)等企业工作，”他表示。“这是一个被忽视的弱势阶层。”

　　That has dragged down median wages, while the wealthiest have seen their earning power rise. At the same time, says Rachel Dwyer, a sociologist at Ohio State University, most job creation has been at the top and bottom of the scale, with fewer jobs in the middle.

　　这拉低了工资的平均水平，而最富裕人群的赚钱能力却有所提升。同时，俄亥俄州立大学(Ohio State University)社会学家雷切尔·德怀尔(Rachel Dwyer)表示，大多数新创造的就业岗位都集中在最顶端和最底层，中间的职位较少。

　　This creates a demand problem, and not just for the US. The decline in median incomes has hit the American consumer, once the engine of the global economy. “A huge question mark hangs over the US and global economy because the ‘Energizer bunnies’ that drove them have run out,” says Prof Reich.

　　这就带来了需求问题，而受冲击的不只是美国。中间收入的下降冲击了一度作为全球经济引擎的美国消费者。“一个巨大的问号悬在美国和世界经济上方，因为推动它们前进的‘劲量兔’（Energizer bunny，指劲量电池广告中的兔子——译者注）的电都耗光了，”赖克教授表示。

　　Dick Longworth of the Chicago Council on Global Affairs, a think-tank, is more categorical. “This is a consumer society and they’re the consumers,” he says. “If they don’t buy, we don’t survive.”

　　 智库芝加哥全球事务委员会(Chicago Council on Global Affairs)的迪克?隆沃思(Dick Longworth)说得更加直接。“这是一个消费社会，而他们是消费者，”他表示。“如果他们不买东西，我们将无法生存。”