Module: Market Share Metrics $2/$ Problem Set ID: $1044$

All$-$over Shampoo is a leading brand in the company's western sales region. Of the $660,000$ households in the region, $500,000$ purchase the shampoo category. Among this group, $211,000$ households purchased All$-$over shampoo. Households that bought All$-$over brand shampoo purchased $575,000$ bottles of All$-$over. Those same households purchased $848,000$ bottles of shampoo in total. The average consumption of households that bought any brand of shampoo was $2\mathrm{.}120oz$ bottles. However, All$-$over is targeted at heavy users.

What is the usage index for households buying All$-$over brand shampoo in their western region?