An analyst estimates there is a probability of $17$ percent that there will be a recession next year. He thinks the probability of things being normal is three times the probability of a recession, with the remaining probability assigned to a boom taking place. A stock is expected to return $-18$ percent in a recession, $11$ percent under normal conditions and $21$ percent if there is a boom. What is the expected return $($in percent$)$ on this stock? Answer to two decimals, carry intermediate calcs. to four decimals.