Year Number 1960 25854 1961 26406 1962 26896 1963 27380 1964 27869 1965 28400 1966 28937 1967 29505 1968 30144 1969 30804 1970 31526 1971 32297 1972 33110 1973 33955 1974 34914 1975 35983 1976 37060 1977 38037 1978 38885 1979 39690 1980 40459 1981 41189 1982 41799 1983 42262 1984 42627 1985 42894 1986 43084 1987 43321 1988 43568 1989 43732 1990 43864 1991 44038 1992 44394 1993 44902 1994 45412 1995 45881 1996 46313 1997 46718 1998 47105 1999 47476 2000 47839 2001 48121 2002 48398 2003 48724 2004 49037 2005 49391 2006 49927 2007 50583 2008 51234 2009 51906 2010 52585 2011 53274 2012 54017 2013 54805 2014 55562 2015 56284 2016 57016 2017 57747 2018 58461 2019 59217 2020 60215 2021 61463 2022 62550 2023 63468