The relevance of this aspect. This field is returned if eBay has data on how many searches have been performed for listings in the category using this item aspect.
Note: This container is restricted to applications that have been granted permission to access this feature. You must submit an App Check ticket to request this access. In the App Check form, add a note to the Application Title/Summary and/or Application Details fields that you want access to 'Buyer Demand Data' in the Taxonomy API.