Year Number 1960 237633 1961 242499 1962 246648 1963 249831 1964 251808 1965 252622 1966 252609 1967 253090 1968 254702 1969 255916 1970 256447 1971 257334 1972 258150 1973 258296 1974 258207 1975 257810 1976 256862 1977 256061 1978 255732 1979 255757 1980 256601 1981 258173 1982 260348 1983 263475 1984 266891 1985 269842 1986 273003 1987 276927 1988 281004 1989 283247 1990 283199 1991 281830 1992 277204 1993 270165 1994 263166 1995 255791 1996 247883 1997 239201 1998 229505 1999 219588 2000 209820 2001 199450 2002 189410 2003 180932 2004 173388 2005 166674 2006 161438 2007 157734 2008 155265 2009 152962 2010 150380 2011 148695 2012 148563 2013 149287 2014 150114 2015 150957 2016 152032 2017 153167 2018 153685 2019 153823 2020 153414 2021 152208 2022 151370 2023 150443