Weeks of supply, or WOS, is a measurement for current inventory levels as it relates to your future demand. WOS acts as a metric to value the life of existing inventory in weeks. In other words, how many weeks it will take for an item to sell out based on current in-pipe inventory and future projected weekly sales. WOS is calculated as inventory on hand divided by future average weekly sales.
When setting up a Weeks of Supply metric, you have a few options:
- View by Store or DC. Store WOS looks at it from the perspective of store in pipe inventory (store on hand + store in transit + store in whse + store on order) where DC WOS uses DC in pipe (whse on hand + whse ss on order)
- N4W Forecast or L4W POS. N4W Forecast will use an average of the next four weeks forecast for the denominator where L4W POS option would use an average of the last 4 weeks unit sales.
Weeks of Supply is generally viewed using the "Latest" time range and as a KPI but can be set up to graph it out over time and look for historical trends.
The "By Item" tab of the expanded view/detail data shows the data rolled up to the item-week level. "By DC" allows you to drill down into individual item-DCs.