step,rule,n_before,n_after,n_removed,rationale
1,drop months before 1992-03-01 (lags of ip_growth / neworder_chg unavailable; spec start),417,415,2,TASK.md training-row definition s >= 1992-03-01
2,drop months s with s+1 > last origin 2026-08-01 (target not in info set),415,413,2,information-availability rule at last origin