In the mid-1990's, the US Department of Housing and Urban Development instituted the Homeless Management Information System, or HMIS, a computerized collection of data on the nation's homeless. The system has been implemented throughout the country, and has been used in Knox County since 2004. Chrissy Keuper speaks with David Patterson, a professor of Social Work at the University of Tennessee and the director of Knox HMIS. Patterson says the number of homeless nationwide has leveled off, but that's not the case in Knox County... 