The Supreme Court Compendium: Data, Decisions, and Developments, 6th ed. (2015) by Start here whenever you need statistics about the Court. This superb collection of data and statistics covers: review process; opinion, decision and outcome trends; justices - background, nomination, confirmation; justices - post-confirmation activities; justices - voting behavior and opinions; Supreme Court - political and legal environment (including information on the Solicitor General); Supreme Court and public opinion; impact of the Court.
You can use Index to Legal Periodicals to find articles about the Court that incorporate statistical analyses.
Use the Advanced Search option. For the first search text box, select "SU Subject Terms" from the adjacent pull-down menu, and enter following exact expression (including the quotation marks and the slash!).
"united states/supreme court"
For the next search text box, leave "Select a Field (optional)" in the adjacent pull-down menu. The enter the following term:
statistic*
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