The number of prisoners in these facilities increased by more than 82,000 in 1989, the largest increase in the 65-year history of the statistical series. The increase equals a demand for 1,600 new prison beds per week nationwide. On December 31, 1989, the number of sentenced prisoners per 100,000 residents in the general population was 274, another new record. Prison populations grew most rapidly in the northeastern states. The female prison population has grown more rapidly than the male population in each year since 1981. Finally, some evidence suggests that the prison population growth may reflect the increased certainty of punishment. Tables and methodological note.