Year % 1988 46.97668 1991 53.3222 1993 31.17543 1996 9.057352 1997 7.960026 1998 7.406605 1999 6.514381 2000 4.747822 2001 6.045896 2002 4.647954 2003 5.78524 2004 4.485978 2005 2.940376 2006 11.87469 2007 14.23996 2008 3.323084 2009 3.436401 2010 3.226696 2011 3.24517 2012 3.265666 2013 4.964063 2014 2.401735 2016 4.065566 2020 9.118407 2021 9.100573