มีผู้ป่วยกี่คนที่อยู่ในหน่วยดูแลผู้ป่วยในปีที่ผ่านมา?ไม่จำเป็นต้องใช้ตารางทั้งหมด
how many patients had been in the careunit sicu during the previous year?It is not neccessary to use all the tables.
 icustays:  row_id [ number]  subject_id [ number]  hadm_id [ number]  icustay_id [ number]  first_careunit [ text]  last_careunit [ text]  first_wardid [ number]  last_wardid [ number]  intime [ time]  outtime [ time] 
SELECT COUNT(DISTINCT admissions.subject_id) FROM admissions WHERE admissions.hadm_id IN (SELECT transfers.hadm_id FROM transfers WHERE transfers.careunit = 'sicu' AND DATETIME(transfers.intime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year'))