Nancy wants to buy zero-coupon bonds as a means of saving for retirement. She finds that the current price of a zero-coupon bond with a face value of $1,000 and 25 years to maturity is $234.80. (Round answer to 0 decimal places, for e.g. 15.25.) (a) If she buys this bond and holds it to maturity, what annual yield to maturity will she earn before taxes?