1- 2026-10-29: P0 passed (contract written).2- 2026-10-29: P1 audit done; one missing value (2025-10). Decision: model = ARIMA(2,1,0) without constant (AR(2) on first differences), Gaussian MLE via Kalman filter (statsmodels SARIMAX), expanding window from 1948-01; chosen a priori, not tuned on evaluation errors.3- 2026-10-29: P2/P3 done: analysis.py written; naive + ARIMA210_nc forecasts, 144 ledger rows.4- 2026-10-29: P4 passed: clean re-run identical; checks.md all PASS; gate run (only P5 artifacts missing).5- 2026-10-29: P5: report.md, claims.json written; final gate run.6- 2026-10-29: Final gate PASSED (receipt 20261030T040120.873744Z). Task complete.7