Group 1: Portfolio Strategy Performance Tracking - The simulated portfolio yields have generally shown marginal decline this week, with the secondary ultra-long and urban investment ultra-long strategies leading in the interest rate style portfolio, yielding 0.2% and 0.18% respectively. In the credit style portfolio, the secondary ultra-long and urban investment ultra-long strategies achieved yields of 0.36% and 0.26% respectively [2][14][15] - The average yield of the credit style time deposit heavy portfolio decreased by 5.2 basis points to 0.11%, indicating a lack of aggressive attributes in recent weeks. The urban investment heavy portfolio's average yield fell by 3.9 basis points to 0.17%, with the duration strategy being the only one showing continuous improvement, achieving an absolute yield of 0.23% [2][18] - The average yield of the secondary capital bond heavy portfolio decreased by 14.3 basis points to 0.18%, benefiting from the rise in ultra-long bond components. The mixed-dumbbell strategy remains superior to other portfolios, while the secondary bond duration strategy slightly outperformed the corresponding interest rate style portfolio but underperformed compared to the similar duration urban investment heavy portfolio [2][18] Group 2: Sources of Returns - Most ultra-long bond heavy strategies derive over 80% of their returns from capital gains. The simulated portfolio's coupon rates have begun to decline, with the credit style secondary bond and secondary ultra-long strategies experiencing a weekly coupon rate drop of over 0.1%. The annualized returns of the urban investment and secondary ultra-long strategies are still 35.9 basis points and 44.7 basis points away from their lowest points since 2025 [3][27] - The contribution of portfolio coupons is concentrated between 15% to 40%, while over 85% of the returns from the secondary ultra-long strategy come from capital gains, effectively amplifying the yield spread [3][27] Group 3: Credit Strategy Excess Returns Tracking - Over the past four weeks, the secondary perpetual bond duration strategy has significantly outperformed, with cumulative excess returns exceeding the benchmark for most strategies. The cumulative excess returns for the secondary bond duration, perpetual bond duration, and perpetual bond sinking strategies reached 22.7 basis points, 18 basis points, and 16.4 basis points respectively [4][32] - In terms of strategy duration, the excess returns of medium to long-term strategies have been narrowing for two consecutive weeks. In the short term, the time deposit strategy and urban investment sinking strategy outperformed the benchmark, with excess returns widening. However, the medium to long-term strategies' excess returns have gradually shrunk, with most strategies underperforming the benchmark by less than 3 basis points [4][35] - For the ultra-long end, the urban investment, industry, and secondary ultra-long combinations achieved excess returns of 8.9 basis points, 8.6 basis points, and 19.6 basis points respectively, indicating a divergence in performance between non-financial credit and secondary bond heavy portfolios [4][35]