For decades, medical investigators would question how the death rates at asylums, including the one in Lincoln, Illinois, could be so high. In the 1990s, the average life expectancy for individuals with mental retardation was 66.2 years. In the 1930s, the average life expectancy for those classified as feebleminded was approximately 18.5 years. Records suggest that a disproportionate percentage of the feebleminded at Lincoln died before the age of ten.
