The Imperfect Intermediation of Money-Like Assets

We study supply-and-demand effects in the U.S. Treasury bill market by comparing the returns on T-bills to the policy rate on the Federal Reserve's reverse repurchase (RRP) facility. We develop and test a simple model where the RRP-bill spread is policed both by heterogeneously elastic money funds and by corporate treasurers who derive collateral benefits from holding T-bills. In response to shifts in T-bill supply, money funds act as front-line arbitrageurs. However, when T-bills become extremely scarce, less elastic corporate treasurers become the marginal investors and supply shifts have a larger effect on T-bill rates.