This paper seeks to explain why annuity purchases are postponed to a later age. We consider an overlapping generations model with uncertain lifetime and two types of annuities. It is shown that, if the economy is dynamically inefficient, individuals demand annuities without delay. However, if it is efficient, annuity purchases are postponed. We also show that these results are robust to several extensions.

中文翻译：

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为什么我们推迟购买年金？

本文试图解释为什么购买年金被推迟到更晚的年龄。我们考虑具有不确定寿命和两种类型年金的重叠世代模型。结果表明，如果经济是动态无效率的，个人会毫不拖延地要求年金。但是，如果有效，则推迟购买年金。我们还表明，这些结果对几个扩展是稳健的。