Reports that at midyear 1997 an estimated 1,725,842 persons were incarcerated in the Nation's prisons and jails. Federal and State prison authorities and local jail authorities held in their custody 645 persons per 100,000 U.S. residents. Prisoners in the custody of the 50 States, the District of Columbia, and the Federal Government accounted for two-thirds of the incarcerated population (1,158,763 inmates). The other third were held in local jails (567,079). On June 30, 1997, 1,218,256 prisoners were under Federal and State jurisdiction (includes prisoners in custody and persons under the legal authority of a prison system but who are held outside its facilities). Local jail authorities held or supervised an estimated 637,319 offenders -- an increase of 7.8% from midyear 1996.