Account statistics shows a high-level overview of usage and similarity statistics for your account. For example, you are able to see the classes with the highest number of submissions for a given period and the classes that have the most submissions with feedback amongst other statistical summaries.
The Common Core Rubric Reports provide detailed statistics about classes that have used Turnitin's Common Core rubrics. Statistics for the Common Core Rubric Reports are available for any six-month or less time period. For example, 1/1/12 to 6/31/12, 1/1/12 to 1/2/12, or 10/15/16 to 3/14/17. Turnitin only supports data date ranges of 1/1/12 and later.