what is the total amount of input until 12/28/2105 patient 23061 had received?
select sum(inputevents_cv.amount) from inputevents_cv where inputevents_cv.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 23061 ) ) and strftime('%y-%m-%d',inputevents_cv.charttime) <= '2105-12-28'