Purchase Frequency: how often you purchase (For example, purchasing once every 30 days)
Default Purchase Days: default estimated time taken from purchase creation to purchase receiving. (For example, 7 days)
Default Safety Days: default buffer time to prevent purchased products from not arriving on time. (For example, if we sell about 50 pieces of paper per day and there are still 150 pieces of available inventory left, we can still sell them for about 3 more days, which is the safety days)
Forecasted Daily Sales: Estimated daily sales of products. (For example, the paper sells about 50 pieces a day)
Sales Coefficient: For example: When the sales on a promotion day are about twice than usual, you can set the Sales Coefficient on this day to 0.5 to make the final average sales more reasonable.
Out of Stock Qty: For example, if the paper has already been oversold by 20 pieces. 20 is the out-of-stock quantity.