Year Number of 1990 1323.87 1991 1353.46 1992 1384.17 1993 1418.37 1994 1454.56 1995 1489.24 1996 1530.79 1997 1574.38 1998 1623.35 1999 1675.47 2000 1734.65 2001 1792.53 2002 1856.81 2003 1923.41 2004 1981.49 2005 2043.16 2006 2077.99 2007 2115.58 2008 2158.63 2009 2204.82 2010 2260.44 2011 2324.87 2012 2395.99 2013 2466.41 2014 2545.27 2015 2633.61 2016 2725.38