Year Number 1990 43408 1991 36236 1992 34888 1993 33515 1994 32242 1995 30933 1996 29687 1997 28490 1998 27304 1999 26114 2000 24894 2001 23662 2002 22486 2003 23906 2004 20651 2005 20141 2006 19900 2007 19755 2008 19702 2009 19765 2010 19779 2011 20787 2012 24392 2013 25246 2014 24703 2015 24777 2016 22823 2017 23103 2018 23760 2019 21117 2020 19632 2021 19727 2022 18552