Pfd Company has debt with a yield to maturity of $8\mathrm{.}24\%,$ a cost of equity of $15\mathrm{.}31\%,$ and a cost of preferred stock of $9\mathrm{.}36\%.$ The market values of its debt, preferred stock, and equity are $$14\mathrm{.}6$ million, $$2\mathrm{.}6$ million, and $$14\mathrm{.}1$ million, respectively, and its tax rate is $28\%.$ What is this firm's after$-$tax WACC?

Note: Assume that the firm will always be able to utilize its full interest tax shield.

Pfd$\text{'}$s after$-$tax WACC is $\%.($Round to two decimal places.$)$