Year Number of 1990 2528.78 1991 2744.03 1992 2981.23 1993 3230.05 1994 3499.32 1995 3789.83 1996 4165.79 1997 4586.03 1998 5060.13 1999 5582.69 2000 6152.05 2001 6337.88 2002 6537.52 2003 6749.59 2004 6975.36 2005 7207.14 2006 7373.51 2007 7549.75 2008 7728.98 2009 7918.54 2010 8112.65 2011 8384.36 2012 8671.59 2013 8970.65 2014 9282.7 2015 9608.75 2016 9947.23