Year Number of 1990 1865.02 1991 1951.34 1992 2032.76 1993 2133.18 1994 2242.62 1995 2355.81 1996 2447.51 1997 2541.99 1998 2619.35 1999 2727.02 2000 2872.54 2001 2999.33 2002 3136.61 2003 3251.9 2004 3398.77 2005 3547.62 2006 3638.52 2007 3763.48 2008 3941.8 2009 4168.24 2010 4380.48 2011 4528.34 2012 4699.07 2013 4858.18 2014 5027.97 2015 5158.26 2016 5283.07