Year Number 1960 16687 1961 17123 1962 17648 1963 18304 1964 19028 1965 19836 1966 20754 1967 21758 1968 22824 1969 23949 1970 25140 1971 26394 1972 27703 1973 28352 1974 27974 1975 27607 1976 27789 1977 28187 1978 28626 1979 29108 1980 29626 1981 30160 1982 30605 1983 30888 1984 31130 1985 31418 1986 31777 1987 32231 1988 32775 1989 33411 1990 34145 1991 34965 1992 35767 1993 36301 1994 36681 1995 37184 1996 37816 1997 38590 1998 39502 1999 40526 2000 41653 2001 42834 2002 43913 2003 44996 2004 46300 2005 47820 2006 49550 2007 51493 2008 53619 2009 55883 2010 58275 2011 60434 2012 62376 2013 64467 2014 66682 2015 68970 2016 71223 2017 73441 2018 75732 2019 78060 2020 80369 2021 82668 2022 85248 2023 88176