Milton Corporation has $7$ percent coupon bonds making annual payments with a YTM of $6\mathrm{.}5$ percent. The current yield on these bonds is $6\mathrm{.}85$ percent. How many years do these bonds have left until they mature? $($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

Maturity of bond

years