Year Number of 1990 608.2 1991 633.1 1992 656.02 1993 666.79 1994 691.68 1995 723.96 1996 758.88 1997 758.52 1998 779.84 1999 800.94 2000 820.57 2001 832.05 2002 827.45 2003 861.47 2004 857.76 2005 865.68 2006 895.39 2007 929.11 2008 986.33 2009 1030.28 2010 1077.03 2011 1144.14 2012 1216.34 2013 1281.07 2014 1354.75 2015 1436.73 2016 1518.48