The present paper derives a money demand function that explicitly takes the costs of storing money into account. This function is then used to examine the consequences of the large-scale money injection conducted by the Bank of Japan since April 2013. The main findings are as follows. First, the opportunity cost of holding money calculated using 1-year government bond yields has been negative since the fourth quarter of 2014 and most recently (2020:Q2) was −0.2%. Second, the marginal cost of storing money, which was 0.3% in the most recent quarter, exceeds the marginal utility of money, which was 0.1%. Third, the optimal quantity of money, measured by the ratio of M1 to nominal gross domestic product, is 1.2. In contrast, the actual money-income ratio in the most recent quarter was 1.8. The welfare loss relative to the maximum welfare obtained under the optimal quantity of money in the most recent quarter was 0.2% of nominal gross domestic product. The findings imply that the Bank of Japan needs to reduce M1 by more than 30%, for example through measures that impose a penalty on holding money.

中文翻译：

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大量注资的福利影响：2013 年至 2020 年的日本经验

本文推导出一个货币需求函数，该函数明确考虑了储存货币的成本。然后使用此函数来检查日本银行自 2013 年 4 月以来进行的大规模注资的后果。主要调查结果如下。首先，使用 1 年期政府债券收益率计算的持有货币的机会成本自 2014 年第四季度以来一直为负，最近（2020 年第二季度）为 -0.2%。其次，存储货币的边际成本在最近一个季度为 0.3%，超过了货币的边际效用，为 0.1%。第三，以 M1 与名义国内生产总值的比率衡量的最佳货币数量是 1.2。相比之下，最近一个季度的实际货币收入比为1.8。最近一个季度在最优货币数量下获得的最大福利的福利损失为名义国内生产总值的0.2%。调查结果表明，日本央行需要将 M1 减少 30% 以上，例如通过对持有货币进行惩罚的措施。