This happened in March, 2019, when the yield curve on 10-year Treasuries fell below that offered on the three-month for the first time in over a decade (or became inverted, see below). The inversion...

This happened in March, 2019, when the yield curve on 10-year Treasuries fell below that offered on the three-month for the first time in over a decade (or became inverted, see below). The inversion was fueled by this hedging activity, which pushed swap rates down further and faster than 10-year Treasury yields.