As of 2012 there were 285 million people who were visually impaired of which 246 million had low vision and 39 million were blind. The majority of people with poor vision are in the developing world and are over the age of 50 years. Rates of visual impairment have decreased since the 1990s.Visual impairments have considerable economic costs both directly due to the cost of treatment and indirectly due to decreased ability to work.ome also include those who have a decreased ability to see because they do not have access to glasses or contact lenses. Visual impairment is often defined as a best corrected visual acuity of worse than either 20/40 or 20/60.