1step,rule,n_before,n_after,n_removed,rationale20_read,rows read from data/firm_panel.csv,2140,2140,0,raw input31_dedupe,drop exact duplicate rows (keep first),2140,2100,40,assembly error: identical firm-year rows repeated42_drop_rating_2025,"remove column rating_2025 (known 2025, uses realised defaults)",2100,2100,0,violates information-availability rule; column removal only53_outcome_observed,drop rows with missing default_next,2100,1800,300,outcome year not observed at data cut (end 2022); no imputation64_complete_predictors,drop rows with missing predictors,1800,1800,0,listwise deletion (none expected)7