The past five monthly returns for Kohls are $3\mathrm{.}86$ percent, $4\mathrm{.}42$ percent, $-2\mathrm{.}00$ percent, $9\mathrm{.}41$ percent, and $-2\mathrm{.}88$ percent. Compute the standard deviation of Kohls' monthly returns.

Note: Do not round intermediate calculations and round your final answer to $2$ decimal places.

Standard deviation