step,rule,n_before,n_after,n_removed,rationale
1,drop rows with missing infl_annualised,127,126,1,first difference undefined for 1995Q1
2,last estimation sample: quarters after last origin 2025-07-01 not used,126,122,4,information-availability rule (quarters <= origin only)
3,"drop first 4 quarters to form lags (common AIC sample, PMAX=4)",122,118,4,lagged regressors undefined at start of sample