We study the cost of breaching an implicit contract in a goods market. Young and Levy (2014) document an implicit contract between the Coca‐Cola Company and its consumers. This implicit contract included a promise of constant quality. We offer two types of evidence of the costs of breach. First, we document a case in 1930 when the Coca‐Cola Company chose to avoid quality adjustment by incurring a permanently higher marginal cost of production, instead of a one‐time increase in the fixed cost. Second, we explore the consequences of the company's 1985 introduction of “New Coke” to replace the original beverage. Using the Hirschman's (1970) model of Exit, Voice, and Loyalty, we argue that the public outcry that followed New Coke's introduction was a response to the implicit contract breach.

中文翻译：

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承诺，信任和背叛：违反隐性合同的成本

我们研究了商品市场中违反隐性合同的成本。Young and Levy（2014）记录了可口可乐公司与其消费者之间的隐性合同。这份隐含的合同保证了质量的恒定。我们提供两种类型的违约成本证据。首先，我们记录了1930年的一个案例，当时可口可乐公司选择通过产生永久性更高的边际生产成本来避免质量调整，而不是一次性增加固定成本。其次，我们探讨了该公司1985年推出的“新可乐”来代替原饮料的后果。使用赫希曼（Hirschman，1970）的退出，声音和忠诚度模型，我们认为，随着新可口可乐的推出，公众的强烈抗议是对隐性合同违约的回应。