The 1-year forward rates f1, f2, f3, f4, f5, f6, f7, f8, f9and f10 are 1.08%, 1.09%, 1.68%, 3.23%, 2.98%, 4.07%, 3.95%, 4.39%, 5.34% and 5.71%, respectively. According to the expectations hypothesis, the expected purchase price of a 4-year 6.62% annual coupon bond with a par value of $1,000 to be purchased in4-year time is $__________.