Simultaneously buying this quantity’s namesake caps and floors is known as this quantity’s so-called “collar” strategy. (-5[1])Indices for this quantity are often the underlying for a forward rate agreement. The TED spread measures the difference between two forms of this quantity. A London-based index for this quantity that was discontinued in June 2023 following its namesake scandal in 2012 (15[1])was named Libor. In one model, output increases as this quantity decreases along the (*) investment-saving curve. Two forms of this quantity are related to the rate of inflation in the Fisher equation, where the real (10[1])form of this quantity approximately equals the nominal form minus (-5[1])inflation (-5[2])rate. (10[1])Decreasing this quantity (10[1])close to zero results in the liquidity trap. For 10 points, identify this quantity, the so-called cost of borrowing money. (10[1])■END■ (10[3])