Larry's Auto Body Repair Shop had revenues that averaged $$47860\mathrm{.}86$ per week in April and $$55954\mathrm{.}80$ per week in May. Assume four weeks per month. During both months, the shop employed six full$-$time $(40$ hours$/$week$)$ workers. In April the firm also had four part$-$time workers working $25$ hours per week, but in May there were only $2$ part$-$time workers and they only worked $10$ hours per week. What is the percentage change in labor productivity from April to May for Larry's Auto Body Repair?