Vaughn Inc. has been using the services of San Bernadino Brokerage Company $($SBBC$)$ for the past six months. SBBC has informed Vaughn Inc. that the geometric mean monthly return was $6\mathrm{.}6$ percent and that over the past six months Vaughn Inc. earned $15\mathrm{.}6$ percent, $18\mathrm{.}6$ percent, $-22\mathrm{.}6$ percent, $13\mathrm{.}6$ percent, $-7\mathrm{.}6$ percent, and an unknown amount in the last month.

Determine the missing return. $($Round intermediate calculations to $6$ decimal places, e$.$g$.1\mathrm{.}251125$ and the final answer to $4$ decimal places, e$.$g$.14\mathrm{.}5125\%.)$

Missing return