Covering the shortfall would cost around ￡120bn a year, equivalent to the budget of the National Health Service. 一年里每周都少上一天班所节省的费用有一千两百亿英镑，相当于英国国民医疗保健制度一年的预算。

　　The Greens' proposals encounter two problems. 但是绿党的提议碰到两个问题。

　　First, the theory. 第一个是理论方面。

　　They argue that the reduced hours worked by some could be redistributed to others in order to lower underemployment. 有的人提出一些人减少的工作时长将会被重新分配给其他人，以此来降低不充分就业。

　　They thus fall prey to the “lump of labour fallacy”, the notion that there is a fixed amount of work to be done which can be shared out in different ways to create fewer or more jobs. 这些人是深受“劳动力臃肿谬论”这一观点困扰；其含义是，需要完成的工作总量是固定的，不过这可以通过不同的方式增加或减少就业机会。

　　In fact, if people worked fewer hours, demand would drop, and so fewer working hours would be on offer. 但事实上，如果人们的工作时间变短，那么对劳动力的需求也会减少，所以劳动力提供的总工作时长也会减少。

　　Second, the cost. 第二是费用。

　　Increased productivity could cover some of the costs of paying a five-day wage for a four-day week, suggests Sarah Lyall of the New Economics Foundation, a think-tank. 智囊团机构新经济基金会的Sarah Lyall表示，提高的生产率可能会由于在四天工作日里支付相当于五天工作日的工资而增加了成本。

　　She points to a Glasgow marketing company that did just that, and experienced a 30% leap in productivity. 她也指出Glasgow营销公司也实行这个政策，他们的生产率也上升了30%。

　　But that is an astonishing increase to expect across the board. 但是各个方面的成本都有了惊人的增长。

　　The Greens say they are in the early stages of exploring the idea and have not yet produced firm costings. 绿党说他们对这个想法的探索还处于初级阶段，也并没有具体分析这个政策是否会影响生产型企业的成本核算。

　　It might be useful to do so before next month's local elections. 在下个月的大选前，他们可能会在党内实行这个政策。

　　That leaves little time—but presumably the party's policymakers will raise their productivity accordingly. 虽然工作时间会减少，但是党内的决策者大概将会相应的提高效率。