Bounding box is created for cutlist items only. You need to create the feature in your component. But it won't end up in your configuration properties. What you show looks like the indented Table of a sheetmetal part. You need to stick to the 2000-SW-version-workaround of flatten-insert sketch with driven dimension-unflatten idea. It's worked for 18 years. We haven't heard of a significant improvement yet. Other options are available but not automatically within the SW menu options. Bounding box also calculates the overall size as is. So if your sheetmetal is bend it won't give you the flat layout but the formed size bounding box area unless you flatten it first.
Thanks for the reply. Yes its a little frustrating that the information is right there, just you cant automate it to show in a bom. I've just voted on the enhancement to hopefully see it in solidworks very soon.