The Days To Sell data is retrieved from AutoTrader and if it's not showing, it's likely that you do not have the Full Retail Check product with AutoTrader. Days To Sell is AutoTrader's prediction of how long it will take to sell a vehicle. The Sold In columns provide the actual time taken to sell a vehicle. Note different versions on the Sold In column are provided for different dates such as Date Added and Date For Sale, these columns can be enabled by selecting the Columns button in the Vehicle -> Browse Vehicles section.