Year Number 1960 13967 1961 14454 1962 14963 1963 15483 1964 16009 1965 16550 1966 17104 1967 17670 1968 18257 1969 18869 1970 19503 1971 20160 1972 20842 1973 21541 1974 22259 1975 22990 1976 23728 1977 24468 1978 25038 1979 25089 1980 25169 1981 25649 1982 26166 1983 26723 1984 27331 1985 27987 1986 28692 1987 29438 1988 30222 1989 31041 1990 31922 1991 32882 1992 33897 1993 34923 1994 35859 1995 36708 1996 37513 1997 38274 1998 38997 1999 39684 2000 40277 2001 40818 2002 41366 2003 41873 2004 42352 2005 42812 2006 43274 2007 43773 2008 44346 2009 44978 2010 45883 2011 47109 2012 48448 2013 49869 2014 51361 2015 52879 2016 54380 2017 55857 2018 57294 2019 58674 2020 59987 2021 61215 2022 62325 2023 63296