Year Number of 1990 5542.07 1991 5770.36 1992 6054.69 1993 6284.77 1994 6535.9 1995 6747.29 1996 6893.26 1997 7048.67 1998 7259.96 1999 7191.88 2000 7138.06 2001 7185.08 2002 7339.32 2003 7517.75 2004 7723.31 2005 8049.1 2006 8375.87 2007 8427.69 2008 8610.76 2009 8814.53 2010 9074.14 2011 9423.74 2012 9397.78 2013 9353.5 2014 9265.59 2015 9610.11 2016 9925.35