This data set from the Office of Children and Family Services (OCFS) provides information, by county, on detention admissions and unique youth admitted to detention from 2006 to most recent year for which data are available.
This chart is based on the data set from the Office of Children and Family Services (OCFS) which provides information on detention admissions and unique youth admitted to detention from 2006 to 2012; the main data set, reported by county, is at https://data.ny.gov/d/ybg9-s6bm