In an economy where banks take numeraire goods, so called money, as deposits, money allows depositors suffering preference shocks to withdraw from banks prematurely without liquidation of real investment. If real liquidity, defined as the real value of the monetary base, is low, the amount of payment liquidity, constrained by the velocity of money, limits the short-term price level of investment goods before banks can settle their long-term loan contracts. This leads to an attractive nominal long-term investment return and over-investment. Allowing for inside money, that is, bank deposits, to be used for payment can improve social welfare but cannot fully resolve the liquidity shortage problem as the short-term interest rate offered by banks is constrained by the threat of bank runs. In the presence of systemic liquidity shocks, the price-adjustment mechanism cannot take full effects with insufficient payment liquidity, which can lead to non-zero profits for banks. Exchanging investment goods for numeraire goods through international trade can improve social welfare.

在一个经济体中，银行将诸如美元之类的货币商品作为存款，存款使遭受偏好冲击的储户过早地从银行撤出，而无需清算实际投资。如果实际流动性（定义为货币基础的实际价值）较低，则受货币流动性限制的付款流动性限制了投资产品的短期价格水平，从而使银行无法偿还其长期贷款合同。这导致有吸引力的名义长期投资回报和过度投资。允许将内部货币，即银行存款用于支付，可以改善社会福利，但不能完全解决流动性短缺问题，因为银行提供的短期利率受到银行挤兑威胁的限制。在出现系统性流动性冲击的情况下，价格调整机制无法在支付流动性不足的情况下充分发挥作用，从而导致银行的非零利润。通过国际贸易将投资商品换成计价商品可以改善社会福利。