Year Number of 1990 2249.8 1991 2274.08 1992 2335.75 1993 2413.5 1994 2463.32 1995 2551.9 1996 2602.15 1997 2651.73 1998 2722.76 1999 2799.84 2000 2806.17 2001 2880.9 2002 2990.03 2003 3110.58 2004 3182.56 2005 3330.13 2006 3392.8 2007 3465.8 2008 3636.57 2009 3826.49 2010 3884.7 2011 3984.68 2012 4169.16 2013 4432.47 2014 4657.98 2015 4767.47 2016 4947.86