The increase for the year brings total growth in the prison population since 1980 to nearly 252,000 inmates -an increase of about 76 percent. The 1987 growth rate of 6.7 percent was less than the 1986 rate of 8.5 percent. Inmates with sentences of more than a year accounted for nearly 96 percent of the population. The number of inmates with sentences over 1 year grew at a faster rate in Federal than in State facilities. In four States, total prison populations decreased during 1987, but in two of these States, declines were small. Total prison population increased most rapidly in Colorado (26.4 percent), Arizona (16 percent), Arkansas (15.8 percent), Michigan (15.1 percent), and Oregon (14.9 percent). In addition, 12 States reported total prisoner increases of 10 percent or more compared to the end of 1986. 12 tables.