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+# Reports framework
+
+A framework that handles querying and rendering tabular data.
+
+TODO: add more details on how each part works.
+
+## Rules
+Rules are used for grouping, ordering, and summary rows. Options are documented at [`Reporting::ReportTemplate#rules`](
+https://github.com/openfoodfoundation/openfoodnetwork/blob/master/lib/reporting/report_template.rb#L68-L95).