Year Number of 1990 704.82 1991 792.41 1992 893.44 1993 991.25 1994 1100.64 1995 1221.99 1996 1338.8 1997 1455.48 1998 1595.2 1999 1701.52 2000 1772.55 2001 1826.04 2002 1877.21 2003 1921.72 2004 1967.1 2005 1998.52 2006 2026.33 2007 2057.16 2008 2091.46 2009 2139 2010 2206.56 2011 2278.79 2012 2351.72 2013 2424.4 2014 2514.87 2015 2615.12 2016 2699.27