What is the difference between Performance Metrics and Page Variables?
Performance Metrics are all of type integer and already aggregated (e.g. by day). They measure the performance of a specific url, e.g. how many times a user visited the page.
Page Variables define a specific state of the page for a given time. It can be integer (e.g. number of headings), holding text (e.g. the Metadescription) or boolean (e.g. if breadcrumbs are present).
