When Show (default) and the Macros module is active with Show Macro Nutrition (global) enabled, subscribers on a Pro or Enterprise plan get a macro-tracking area: a Macros step in the account-member edit pop-up on their subscription page, and a Macro Tracking link in their account menu that opens the customer stats page. Set to Hide to remove the menu link and the Macros step from the edit pop-up. It has no effect if the Macros module is not active. (In the current version a separate, normally-on internal setting can still let the stats page itself render if opened directly, even with this set to Hide - the practical effect for most stores is that Hide removes the link and the pop-up step, which is how customers would reach it.)