instruction: what is the minimum cost of a hospital that involves a idiopath pulmon fibrosis until 4 years ago?
response: SELECT MIN(t1.c1) FROM (SELECT SUM(cost.cost) AS c1 FROM cost WHERE cost.hadm_id IN (SELECT diagnoses_icd.hadm_id FROM diagnoses_icd WHERE diagnoses_icd.icd9_code = (SELECT d_icd_diagnoses.icd9_code FROM d_icd_diagnoses WHERE d_icd_diagnoses.short_title = 'idiopath pulmon fibrosis')) AND DATETIME(cost.chargetime) <= DATETIME(CURRENT_TIME(), '-4 year') GROUP BY cost.hadm_id) AS t1