Year Number of 1990 1329.36 1991 1336.17 1992 1349.76 1993 1365.6 1994 1389.45 1995 1405.18 1996 1417 1997 1426.75 1998 1431.64 1999 1447.68 2000 1464.78 2001 1487.2 2002 1523.08 2003 1555.54 2004 1599.93 2005 1624.71 2006 1661.79 2007 1708.04 2008 1840.21 2009 1944.51 2010 2039.92 2011 2099.89 2012 2151.34 2013 2226.29 2014 2286.83 2015 2355.03 2016 2426.7