What is the yield to call of a 20-year to maturity bond that pays a coupon rate of 16.96 percent per year, has a $1,000 par value, and is currently priced at $927? The bond can be called back in 8 years at a call price $1, 094. Assume annual coupon payments. Round the answer to two decimal places in percentage form. (Write the percentage sign in the "units" box)