The number of 1987 releases was 2 percent over 1986 releases and 56 percent over 1983 releases. The number of males released during 1987 increased 4 percent from 1986, and the number of females released decreased by 2 percent. Fifty-six percent of all releases were by parole, 35 percent were by discharge, and 9 percent were by expiration of sentence. Fifty-one percent were released from maximum-security or medium-security facilities, and 49 percent were released from lower security facilities. Many of those released from secure facilities were females serving county sentences or were male parole violators. The average time served was 52.1 months for those released from Cedar Junction, 19.2 months for those serving Concord sentences, and 6.1 months for those serving Framingham sentences. Tables, glossary. (Author abstract modified)