Year Number 1993 46.70382 1994 42.73302 1995 43.17817 1996 40.16961 1999 38.14266 2000 37.07681 2001 37.73186 2002 39.67494 2003 40.38001 2004 40.47697 2007 47.61001 2008 51.73333 2010 39.85251 2011 36.92924 2012 37.10858 2013 36.18234 2014 35.3968 2015 35.05985 2016 34.95006 2017 34.03857 2019 31.99445