What is the difference between Cu content and min recovery rate?

Hi guys,

I've been reading into the recent news about the Chinese government lifting the restrictions on the importation of high purity scrap metals. If you follow this link it'll take you to one of the articles I've been reading. At the bottom of the article, there's a table which outlines the different categories of copper and brass. Cu content is obviously the amount of copper content in the entire shipment but I can't seem to work out what 'Min. recovery rate (%)' means. Can somebody please clarify for me?