For a specific stock $j,$ the following data are provided.

$\backslash$table$[[,$Prob,Ret$],[$Very good,$0\mathrm{.}05,0\mathrm{.}36],[$Good$,0\mathrm{.}20,0\mathrm{.}28],[$Okay$,0\mathrm{.}50,0\mathrm{.}23],[$Bad$,0\mathrm{.}20,-0\mathrm{.}02],[$Very bad,$0\mathrm{.}05,-0\mathrm{.}14],[$Sum$,1\mathrm{.}00,],[E(r_m)=0\mathrm{.}069$