Year Number of 1990 3823.73 1991 3922.21 1992 4073.63 1993 4224.42 1994 4327.03 1995 4434.06 1996 4451.92 1997 4563.97 1998 4650.46 1999 4638.87 2000 4606.54 2001 4615.92 2002 4745.5 2003 4845.92 2004 4836.71 2005 4973.72 2006 4872.94 2007 4797.43 2008 4963.81 2009 4994.18 2010 5023.17 2011 4990.91 2012 5019.93 2013 5185.54 2014 5232.54 2015 5266.62 2016 5438.25