Year Number 1960 269316 1961 278685 1962 287646 1963 296041 1964 303781 1965 310799 1966 317055 1967 322549 1968 327348 1969 331561 1970 335293 1971 337791 1972 339017 1973 339656 1974 339719 1975 339271 1976 338345 1977 336966 1978 335098 1979 332609 1980 329322 1981 324363 1982 318076 1983 311683 1984 305308 1985 299049 1986 293004 1987 287268 1988 281983 1989 277312 1990 273271 1991 270496 1992 269701 1993 270078 1994 270735 1995 271627 1996 272724 1997 273947 1998 275217 1999 276392 2000 277302 2001 277798 2002 277764 2003 276397 2004 273605 2005 270005 2006 265313 2007 259773 2008 253904 2009 247822 2010 241653 2011 235546 2012 230900 2013 228723 2014 227782 2015 227146 2016 226835 2017 226872 2018 228580 2019 229880 2020 230167 2021 231014 2022 231411 2023 231589