The Missouri Securities Division has also identified investor diminished capacity and senior investor education as crucial issues in the fight against senior investor fraud. Persons with mild diminished capacity can perform most daily functions, but may become confused when managing their finances. This, in turn, makes those individuals more susceptible to fraud. According to a 2008 Duke University study, about 35 percent of the 25 million people in the United States who are 71 or older either have mild cognitive impairment or dementia. Another study indicates that about half the population between ages eighty and ninety has a medical.