Between 1925-39, the number of sentenced prisoners grew annually by 5 percent, substantially higher than for the entire 57-year period. After declining during both wartime periods, the prison population began a dramatic rise in 1974, and by 1982 had reached an incarceration rate of 169 per 100,000 population. In 1926, the National Prisoner Statistics program began to collect statistics on prisoners on an annual basis. The program has been revised over the years to include new categories and to eliminate others. Race and ethnicity, short sentences, and jurisdiction were added. Tabular and graphic data are included.