Decompose portfolio returns into explainable components to identify where value was added or lost. Use when the user asks about Brinson attribution, allocation vs selection effects, factor-based attribution, fixed-income attribution, or currency attribution. Also trigger when users mention 'what drove my returns', 'was it stock picking or sector bets', 'alpha decomposition', 'multi-period linking', 'interaction effect', 'active return breakdown', or ask why their portfolio outperformed or underperformed the benchmark.
