4. Forecasting Interest Rates On May 23, 20XX, the existing or current (spot) one-year, two-year, three-year, and four-year zero-coupon Treasury security rates were as follows: 1/1 - 5.250% IRe - 5.75, 1Rg -6.250% 121-6.45% Using the unbiased expectations theory, what is the one-year forward rate on zero-coupon Treasury bonds for year four as of May 23 (i.e., , f) , 20XX (1 point)