Using statistical process control, the UCL and LCL for an x$-$bar chart are $25\mathrm{.}6$ and $15\mathrm{.}9$ respectively. The central line is $20.$ The results of the next six sample means $($i$.$e$.,$ averages$)$ are $18\mathrm{.}2,23\mathrm{.}3,17\mathrm{.}9,21\mathrm{.}5,24\mathrm{.}5,$ and $16\mathrm{.}6.$ Based on just this information, what should you do$?$