Secondly, we may also define a new procedure after a few months (approx. 3 months) of sell out. With a sales history of 3 months, we have enough data to predict future sell out per counter. Consequently, with an average product life span of total 8 months until call back, we can stock the counter with a bit more than 5 months coverage (enough to last until call back). Or, to be more exact, after 3 months of sell-out, optimal stock coverage is 7.5 months (based on a total 75% sell-through target).