Year Number 1960 30736 1961 31198 1962 31501 1963 31766 1964 31892 1965 31937 1966 32040 1967 32181 1968 32383 1969 32673 1970 33130 1971 33594 1972 33891 1973 34129 1974 34407 1975 34783 1976 35257 1977 35806 1978 36391 1979 36980 1980 37555 1981 38106 1982 38634 1983 39143 1984 39495 1985 39562 1986 39480 1987 39355 1988 39179 1989 38957 1990 38733 1991 39088 1992 40082 1993 41133 1994 42175 1995 43250 1996 44344 1997 45465 1998 46598 1999 47701 2000 48744 2001 49724 2002 50669 2003 51588 2004 52527 2005 53566 2006 54658 2007 55782 2008 56946 2009 58105 2010 59233 2011 60310 2012 61317 2013 62205 2014 62954 2015 63659 2016 64268 2017 64742 2018 65183 2019 65573 2020 65896 2021 66173 2022 66416 2023 66665