Predictive purchasing can help you forecast how much quantity to order for a predicted amount of future sales. The projection is based on a number of factors, including the number of past sales and the available quantity. The past sales is used to determine a velocity, or the rate of sale per day over a given date range. The velocity is then multiplied to calculate the deficit supply for multiple date ranges. In more complex cases the days in stock and on order quantities are also factored into the prediction.

See below important client settings related to predictive purchasing.

Key Terms
• Days OF Order - Days of past sales from which you are basing the prediction. This generates a daily velocity. Please note that days with no stock availability will be skipped in the Days Of Order Count.
• Velocity - Rate of sales per day when calculated by - Qty Sold in Days of Order divided by Days of Order
• Deficit Supply The predicted deficit to your supply for multiple date ranges. This is calculated as follows: (Velocity x Deficit Days) - (Available quantity + On Order) See below.
• Days TO Order - Days to which you are multiplying the daily velocity to generate an Add to PO Qty. While the deficit supply will be calculated for all dates, this selection enables a quick add to PO. See below.
Example:
Days of Order 30/ Days To Order 15

In this example, 108 units sold in the past 30 days (as seen in the Qty Sold field). Because it is based off a 30 period, the per day velocity is 3.6.
• Deficit Supply 15 - Multiplying 3.6 by 15 gives you 54. Subtract the available qty of 28. This gives you a Deficit 15 of 26. ((108/30) * 15) - 28 = 26
• Deficit Supply 30 - Multiplying 3.6 by 30 gives you 108. Subtract the available qty of 28. This gives you a Deficit 30 of 80 ((108/30) * 30) - 28 = 80
• Deficit Supply 45 - Multiplying 3.6 by 45 gives you 162. Subtract the available qty of 28. This gives you a Deficit 45 of 134. ((108/30) * 45) - 28 = 134
• Same calc. for 60 and 90. See below for explanation of 11/M.
Because "Days To Order 15" was selected, the deficit qty of 26 was auto entered into the QTY. field to add to a PO.

Generate a Purchase Prediction
Purchasing predictions can be generated automatically on schedule. Enable the client setting Calculate Qty Sold in X days for Predicted Purchasing. Additionally, the service ProductInventoryMovementService must be running on the server. The service runs once a day around 2 AM. Then, navigate to Inventory > Predicted Purchasing and begin from step 4 below.

To generate manually for the most current data, follow the steps below:
1. Navigate Inventory > Predicted Purchasing.
2. If the services above have been set, proceed to step 5. If not, or you want to calculate based on even more recent data, open the action menu and select Generate Data for Sold Since Last Year, and GO. This action will calculate data for all FBA products in your catalog. Alternatively, you can select specific items on the grid and select Generate Data for Selected SKUs from the action menuSKUs will only display in the grid after steps 5 and 6 have been completed.
3. After the job completes, refresh the page.
4. Select the Days Of Order/Days To Order from their respective dropdowns.
5. You can check the Only show rows with quantity to be ordered to only display items with deficit quantities.
6. See below in "Client Setting" section for explanation of warehouse filters.
7. Press Search and the grid will populate items with the following columns:
1. ProductID
2. ProductName
3. ASIN
4. Avail. Qty - Quantity in all sellable warehouses.
5. Qty - In this field you can enter the quantity to add to a purchase order. See below.
6. Velocity - Rate of sales per day when calculated by  - Qty Sold in Days of Order divided by Days of Order
7. Qty Sold - The quantity sold in the selected "Days of Order". Based on client setting above, it will calculate sales of on days inventory availability. This means that if there were days within the selected "Days of Order" where there was no available inventory, those days will be skipped in the count.
8. Deficit Supply - The predicted deficit to your supply. This is calculated as follows: (Velocity x Days To Order) - (Available quantity + On Order)
9. 11/M Qty Sold 11 months back in time for a full month period. This can be helpful when trying to determine quantities to order for seasonal periods, which are often different than preceding non-season months. For example, if you are at the beginning of November and want to determine how much to order for the coming seasonal month of December, this column will look back 11 months - to December - and display quantity sold for the month of December. This can be used as an indicator if you need to order more qty than was calculated based on the regular velocity.
10. On Order - shows how many units are on open Purchase Orders. PO must be set as "Approved" to consider qty "On Order". It is critical for determining if, and how many units, need to be ordered. After determining how many units are needed for the given time period, both the available quantity and on order quantities are factored in to determine how many need to still be ordered. Clicking on the OnOrder Quantity will open the related PO.
11. Vendor - The default vendor on the product.
12. Vendor Price - The price of the default vendor.
13. Amazon BuyBox Price - The retail price of the BuyBox on Amazon. Many online sellers will use this info to determine if they can be competitive on a given product, or if they should discontinue the product. Read how to get the Amazon BuyBox here.

1. The Deficit quantity based on the Days To Order selection will auto populate in the QTY field. You can edit the filed as necessary.
2. Select the products on the grid.