EX $10-28($Algo$)$ Cost Variance Investigation $($LO $10-4)$

The director of cost management for Odessa Company uses a statistical control chart to help management determine when to investigate variances. The critical value is $1$ standard deviation. The company incurred the following direct$-$labor efficiency variances during the first six months of the current year.

$\backslash$table$[[$January$,$$$420F$