Year per 1,000 uninfected population ages 15-49 1990 0.6 1991 0.7 1992 0.9 1993 1 1994 1.1 1995 1.2 1996 1.3 1997 1.5 1998 1.5 1999 1.7 2000 1.7 2001 1.8 2002 1.9 2003 1.9 2004 2 2005 2 2006 2 2007 2 2008 2 2009 2 2010 1.9 2011 1.9 2012 1.9 2013 1.9 2014 1.8 2015 1.7 2016 1.7 2017 1.6 2018 1.6