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:

1R1 = 5.40%, 1R2 = 5.90%, 1R3 = 6.40%, 1R4 = 6.60%

Using the unbiased expectations theory, what is the one-year forward rate on zero-coupon Treasury bonds for year four as of May 23, 20XX 6.075% 6.60% 7.20% 22.51%