whats the first value of mchc in 10/2103 for patient 70206?
select labevents.valuenum from labevents where labevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 70206 ) and labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = 'mchc' ) and strftime('%y-%m',labevents.charttime) = '2103-10' order by labevents.charttime asc limit 1