Consider the following information:

$\backslash$table$[[$State of Economy,Probability of State of Economy,$\backslash$table$[[$Security Returns if State Occurs$],[($Stock A$)]],\backslash$table$[[$Security Returns if State Occurs$],[($Stock B$)]],\backslash$table$[[$Security Returns if State Occurs$],[($Stock C$)]]],[$Boom$,\mathrm{.}10,\mathrm{.}18,\mathrm{.}48,\mathrm{.}33],[$Good$,?,\mathrm{.}11,\mathrm{.}18,\mathrm{.}15],[$Poor$,\mathrm{.}40,\mathrm{.}05,-\mathrm{.}09,-\mathrm{.}05],[$Bust$,\mathrm{.}30,-\mathrm{.}03,-\mathrm{.}32,-\mathrm{.}09]]$

Your portfolio is invested $30$ percent each in Stocks A and $C$ and the rest in Stock B$.$ What is the percentage standard deviation of the portfolio?