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+# Leaderboards
+
+## Recalculation
+
+To figure out if a Leaderboard needs recalculation, the easiest way is to get
+the transaction set that it corresponds to, and compare either the sum or count
+of that result set to the sum of the leaderboard values.
+
+This can be done at any time, but if recalculation is needed then ALL
+leaderboards newer than one that doesnt match (of the same type) will need
+recalculating due to possible position changes, and therefore the trend
+changing.