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Returns, for the window, the total number of transactions, the count of each status the ledger knows, and the settled volume per asset. Volume sums transaction.amount over SETTLED transactions only — status APPROVED, the only status whose transactions moved money — and is reported PER ASSET with no cross-asset total, because adding two assets together does not produce money. Amounts are exact decimal strings whose scale is not normative; format them with the asset’s own exponent and never parse them as a binary float. volumeByAsset is the GROSS settled amount: every settled leg inside the window, reversal legs included. reversalsByAsset is the part of it made of reversal legs, same window and same settled filter. A true net is NOT derivable from the two alone, because it depends on whether each reversed original also falls inside the window; a consumer that needs net reads the transactions.