what is the yearly minimum amount of cortisol patient 3267 has until 51 months ago?
select min(labevents.valuenum) from labevents where labevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 3267 ) and labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = 'cortisol' ) and datetime(labevents.charttime) <= datetime(current_time,'-51 month') group by strftime('%y',labevents.charttime)