1[2 {"id": "C1", "text": "In real time, the naive last-value forecast had RMSE 2.01 pp (h=1) and 2.27 pp (h=2) against first releases over 8 origins 2024-01-31 to 2025-12-31.", "results_keys": ["rmse_naive_h1", "rmse_naive_h2", "mae_naive_h1", "mae_naive_h2"], "status": "supported", "caveat": "Only 8 origins in an unusual 2024-2025 window."},3 {"id": "C2", "text": "An AR(1) estimated on each real-time vintage (1985Q1 onward, excluding 2020Q2-Q3) lowered RMSE relative to naive by 26% at h=1 and 38% at h=2.", "results_keys": ["rmse_model_h1", "rmse_model_h2", "rel_improvement_rmse_h1", "rel_improvement_rmse_h2"], "status": "supported", "caveat": "Diebold-Mariano tests not significant (p=0.18, 0.12); see supplementary.json."},4 {"id": "C3", "text": "The AR(1) advantage over naive is statistically significant.", "results_keys": ["rel_improvement_rmse_h1", "rel_improvement_rmse_h2"], "status": "unsupported", "caveat": "HLN-corrected DM p-values 0.18 (h=1) and 0.12 (h=2) with n=8."},5 {"id": "C4", "text": "First releases of the h=1 target quarters were subsequently revised by 0.56 pp on average (absolute) by the 2026-10-30 vintage.", "results_keys": ["mean_abs_revision_h1_targets"], "status": "supported", "caveat": "Uses current_vintage.csv only for this statistic; later revisions may still occur."}6]7