Year per Person 1980 2.50826 1981 3.84896 1982 3.76311 1983 6.17683 1984 6.41643 1985 6.47999 1986 6.3545 1987 6.23687 1988 6.10485 1989 5.98278 1990 5.87059 1991 6.07427 1992 5.99835 1993 5.71432 1994 5.6471 1995 5.57845 1996 5.79541 1997 5.74017 1998 5.70508 1999 5.67201 2000 5.60359 2001 6.65909 2002 8.49593 2003 7.65356 2004 9.07981 2005 9.98709 2006 9.91269 2007 9.04931 2008 6.28075 2009 6.01293 2010 3.96743 2011 3.93626 2012 4.99844 2013 9.22843 2014 9.15857 2015 9.07477 2016 20.23268