Year Number of 1990 144.3 1991 151.22 1992 159.07 1993 161.06 1994 167.99 1995 178.08 1996 185.6 1997 194.51 1998 196.74 1999 202.29 2000 210.01 2001 222.93 2002 233.33 2003 244.22 2004 254.95 2005 268.45 2006 281.17 2007 298.15 2008 313.2 2009 329.94 2010 347.36 2011 356.22 2012 365.38 2013 369.06 2014 373.06 2015 379.12 2016 387.47