Year per 1,000 uninfected population ages 15-49 1990 1.6 1991 1.7 1992 2 1993 2.1 1994 2.3 1995 2.3 1996 2.3 1997 2.2 1998 2.1 1999 2 2000 1.9 2001 1.8 2002 1.7 2003 1.6 2004 1.5 2005 1.4 2006 1.4 2007 1.3 2008 1.4 2009 1.3 2010 1.2 2011 1.1 2012 1.1 2013 1 2014 1 2015 1 2016 0.9 2017 0.9 2018 0.8