Year Number of 1990 2350.19 1991 2402.51 1992 2458.98 1993 2500.76 1994 2528.8 1995 2568.01 1996 2594.39 1997 2636.08 1998 2673.86 1999 2698.59 2000 2733.04 2001 2767.54 2002 2798.45 2003 2826.71 2004 2859.12 2005 2890.88 2006 2948.65 2007 3005.1 2008 3054.07 2009 3103.12 2010 3173.35 2011 3257.97 2012 3316.72 2013 3350.69 2014 3390.18 2015 3447.81 2016 3519.25