Change in Prevalence, Blindness, Age 40 and Older
"Legal blindness" represents an artificial distinction and has little value for rehabilitation, but it is significant in that it determines eligibility for certain disability benefits from the federal government. In the United States, it is typically defined as visual acuity with best correction in the better eye worse than or equal to 20/200 or a visual field extent of less than 20 degrees in diameter. These overly simple criteria for visual impairment are far from comprehensive in defining the visual function deficits that can cause difficulties for daily living tasks.
Almost everyone with blindness or vision impairment can benefit from vision rehabilitation, which can help make the most of whatever vision remains.
Unfortunately, blindness and vision impairment represent a significant burden, not only to those affected by sight loss, but to our national economy as well. Prevent Blindness America's 2007 study, The Economic Impact of Vision Problems: The Toll of Major Adult Eye Disorders, Visual Impairment and Blindness on the U.S. Economy estimates the costs associated with adult vision problems in the United States at $51.4 billion.
Blindness, as defined above, affects nearly 1.3 million Americans age 40 and older. The prevalence of blindness increases rapidly in the later years, particularly after age 75.