A bond is issued with a coupon of $5\%$ paid annually, a maturity of $37$ years, and a yield to maturity of $8\%.$ What rate of return will be earned by an investor who purchases the bond for $$646\mathrm{.}74$ and holds it for $1$ year if the bond$$s yield to maturity at the end of the year is $9\%?$ Note: Do not round intermediate calculations. Enter your answer as a percent rounded to $2$ decimal places. Negative amount should be indicated by a minus sign.