According to a 2015 assessment by the U.S. Department of Housing and Urban Development, 564,708 people were homeless on a given night in the United States.

            

At a minimum, 140,000 or 25 percent of these people were seriously mentally ill, and 250,000 or 45 percent had any mental illness.

By comparison, a 2016 study found that 4.2 percent of U.S. adults have been diagnosed with a serious mental illness. – BBRfoundation