Year Number of 1990 1415.03 1991 1549.3 1992 1680.76 1993 1807.72 1994 1920.36 1995 1998.69 1996 2077.72 1997 2169.99 1998 2295.27 1999 2429.46 2000 2530.89 2001 2638.2 2002 2792.15 2003 2922.92 2004 3052.43 2005 3165.42 2006 3275.65 2007 3370.29 2008 3494.86 2009 3619.41 2010 3746.18 2011 3810.66 2012 3924.81 2013 4061.32 2014 4204 2015 4366.55 2016 4536.08