what was the last procedure time patient 26817 has had since 2 years ago?
select procedures_icd.charttime from procedures_icd where procedures_icd.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 26817 ) and datetime(procedures_icd.charttime) >= datetime(current_time,'-2 year') order by procedures_icd.charttime desc limit 1