Gold criteria for very severe airflow obstruction in COPD is
FEV1/FVC<0.7 & FEV1>=80% predicted FEV1/FVC<0.7 & >=50% FEV1 but <80% predicted FEV1/FVC<0.7 & FEV1>=30% but <50% predicted FEV1/FVC<0.7 and FEV1<30% predicted