This page provides answers to common questions regarding the Inventory Performance Index (IPI).
IPI score measures how efficient and productive you are in managing your FBA inventory. Multiple factors can influence your IPI score, but it’s important to do the following:
Your IPI score is designed to represent your overall inventory performance. When you take actions to improve your inventory efficiency, they can take time to result an improved IPI score.
While everyone’s business is different, we recommend the following general guidelines to manage your inventory performance:
New ASINs in their first 90 days don’t affect your IPI score.
Once a removal order request is placed, the inventory no longer affects your IPI score. Remember that actions taken today, such a removal order, will take time to be reflected in your IPI score.
In calculating IPI, we consider an item excess or overstock if it has over 90 days of supply based on the forecasted demand.
You can improve your sell-through by increasing sales in relation to your in-stock inventory or removing inventory that is not selling. To improve sales, review your pricing and consider one or more of these options:
If you ship a lot of inventory to Amazon over a certain period, your sell-through could be affected if your sales don’t keep pace with your shipments.
Sell-through rate is updated daily based on the past 90 days of shipped units and average inventory over that same period. We encourage you to try to maintain a sell-through rate in the green (or “good” rating) year round.
Your FBA sell-through rate is your sold and shipped units over the past 90 days divided by the average number of units in stock in our fulfilment centres during that period. We calculate your available average units by taking a snapshot of your inventory levels today and 30, 60, and 90 days ago. For example: Let’s say that you shipped 120 units in the past 90 days and had an average of 80 units available during that period. Your sell-through rate would be 120 divided by 80, which equals 1.5, as shown below.
|Total units sold (cumulative) in past 90 days||120 units|
|Date||Today||30 days ago||60 days ago||90 days ago|
|Inventory available||80 units||150 units
(new shipment of 150 units received)
|40 units||50 units|
Average available inventory = (50 + 40 + 150 + 80) / 4 = 80 units
Sell-through rate = 120/80 = 1.5
An IPI score is available only if you have a Professional selling plan, inventory at a fulfilment centre, and recent account activity. If you are new to FBA or have not been active in the past 13 weeks, you may not have an IPI score until more data becomes available.
In-stock rate is not included as one of the influencing factors. This rate indicates in general how well you replenish your inventory to meet customer demand. A low in-stock rate does not affect your IPI score unless your most popular products consistently go out of stock and the products that remain in stock have low sales, are aged, or are overstocked.
To be considered excess inventory, a product must have at least one unit over 90 days old or more than 90 days of supply. It’s possible that your inventory is not yet old enough to be considered excess but that you have sent in enough inventory to affect your sell-through rate.