Ying Import has several bond issues outstanding, each making semiannual interest payments. The bonds are listed in the table below.

Bond Coupon Rate Price Quote Maturity Face Value

$1.8\mathrm{.}60\%105\mathrm{.}66$ years $ $26,000,000$

$2.6\mathrm{.}8094\mathrm{.}89$ years $46,000,000$

$3.8\mathrm{.}30104\mathrm{.}416\mathrm{.}5$ years $51,000,000$

$4.8\mathrm{.}80106\mathrm{.}326$ years $66,000,000$

If the corporate tax rate is $21$ percent, what is the aftertax cost of the company$$s debt?