Year Number of 1990 1188.07 1991 1223.2 1992 1260.79 1993 1304.63 1994 1352.03 1995 1400.72 1996 1431.3 1997 1473.56 1998 1499.14 1999 1517.45 2000 1560.33 2001 1578.71 2002 1613.59 2003 1658.87 2004 1717.49 2005 1782.52 2006 1862.21 2007 1934.23 2008 2019.11 2009 2115.6 2010 2215.92 2011 2310.73 2012 2408.08 2013 2512.65 2014 2618.86 2015 2723.83 2016 2829.42