Sofia purchases a $$6,000\mathrm{.}006\mathrm{.}45\%$ eight$-$year

par$-$value bond with annual coupons. If held

to maturity, her yield is $6\mathrm{.}6\%.$ The bond is

callable at the end of two years for $$6,300\mathrm{.}00$

and at the end of years five, six, and seven for

$$6,200\mathrm{.}00.$ Find Sofia's minimal yield for the

period she holds the bond.

Round your answer to three decimal places.

Answer in units of percent. Your answer

must be within $+-0\mathrm{.}0\%$