Google will average “only the top ranking that a URL from your website seemed in,” whereas antecedently Google reported the average ranking position of pages on your website that antecedently in Google’s search outcomes for a specific query. Google proffered this instance:
Let’s say Nick searched for [bacon] and URLs from your site seemed in positions 3, 6, and 12. Jane also searched for [bacon] and URLs from your site appeared in positions 5 and 9. Previously, we would have averaged all these positions together and shown an Average Position of 7. Going forward, we’ll only average the highest position your site appeared in for each search (3 for Nick’s search and 5 for Jane’s search), for an Average Position of 4.
Google underlined that historical data won’t change.