Year Total 1960 0 1965 0 1970 0 1975 0 1976 0 1977 0 1978 0 1979 0 1980 0 1981 0 1982 0 1983 0 1984 0 1985 0 1986 0 1987 0 1988 0 1989 0 1990 0 1991 0 1992 0 1993 0 1994 0 1995 0 1996 525 1997 1503 1998 2730 1999 5036 2000 25245 2001 76186 2002 111013 2003 238094 2004 395939 2005 633554 2006 1016605 2007 1858038 2008 3024150 2009 3823625 2010 5707850 2011 7682100 2012 9976105 2013 11240886 2014 12494391 2015 14446897 2016 15404040 2017 17946375