1[2 {"id":"C1","text":"Real-time RMSE of the naive forecast vs first releases is 2.01 pp at h=1 and 2.27 pp at h=2.","results_keys":["rmse_naive_h1","rmse_naive_h2","mae_naive_h1","mae_naive_h2"],"status":"supported","caveat":"Only 8 origins (2024-2025)."},3 {"id":"C2","text":"An AR(1) estimated on each vintage (COVID quarters excluded) has lower RMSE than naive: 1.61 vs 2.01 at h=1 and 1.59 vs 2.27 at h=2 (relative improvement 0.20 and 0.30).","results_keys":["rmse_model_h1","rmse_model_h2","rel_improvement_rmse_h1","rel_improvement_rmse_h2"],"status":"supported","caveat":"Point estimates only; driven largely by the 2025-04-30 origin (LOO improvement ~0.04-0.05)."},4 {"id":"C3","text":"The AR(1) advantage over naive is not statistically significant (HLN-corrected DM p=0.33 at h=1, p=0.26 at h=2).","results_keys":["diebold_mariano_hln"],"status":"supported","caveat":"DM test has low power and approximate size with 8 observations."},5 {"id":"C4","text":"First releases of the h=1 target quarters were later revised by 0.56 pp on average in absolute value, about a third of the forecast RMSE.","results_keys":["mean_abs_revision_h1_targets"],"status":"supported","caveat":"Current vintage (2026-10-30) values may be revised further; recent quarters have had fewer revisions."}6]7