Year % 1989 17.72 1990 18.15 1993 14.51 1995 13.11 1996 9.36 1997 18 1998 6.88 1999 8.11 2000 6.71 2001 5.21 2002 4.69 2003 5.14 2004 5.27 2005 5.29 2006 4.65 2007 3.73 2008 5.44 2009 2.41 2010 2.96 2011 3.12 2012 3.08 2013 2.94 2016 2.78 2017 1.95 2018 1.9 2019 1.82 2020 1.8 2021 1.68