Gain a better understanding of how your customers are evaluating your business on the web with Reviews analytics. You’ll see which sites users are using to review your business and the average score of reviews of your business.
To access Reviews analytics, click Reviews on the left-side navigation panel, then choose the Reviews analytics tab.
Volume of reviews: Displays a breakdown of some of the sites your customers are using to review your business.
Rating stats: Tracks both the average and the distribution of ratings of your business across the web, including reviews by Google users. Because this review score is a simple average of Google and web reviews, it may be slightly different than the rating you see on Google.com or Google+. Additionally, reviews in your inbox that do not include ratings aren’t included in these rating stats.