instruction: how much is the average total hospital cost that includes s/p thoracoscopic procedure - lung reduction since 2105?
response: SELECT AVG(t1.c1) FROM (SELECT SUM(cost.cost) AS c1 FROM cost WHERE cost.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.patientunitstayid IN (SELECT diagnosis.patientunitstayid FROM diagnosis WHERE diagnosis.diagnosisname = 's/p thoracoscopic procedure - lung reduction')) AND STRFTIME('%y', cost.chargetime) >= '2105' GROUP BY cost.patienthealthsystemstayid) AS t1