what was the total of the cerebral drain r ventricular drain output that patient 94937 had on 12/27/last year?
select sum(outputevents.value) from outputevents where outputevents.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 94937 ) ) and outputevents.itemid in ( select d_items.itemid from d_items where d_items.label = 'cerebral drain r ventricular drain' and d_items.linksto = 'outputevents' ) and datetime(outputevents.charttime,'start of year') = datetime(current_time,'start of year','-1 year') and strftime('%m-%d',outputevents.charttime) = '12-27'