Year Number 1960 200720 1961 203605 1962 206389 1963 209626 1964 214284 1965 220161 1966 227123 1967 235149 1968 243863 1969 252944 1970 262023 1971 271257 1972 280270 1973 288976 1974 297167 1975 303973 1976 309751 1977 314824 1978 318710 1979 319898 1980 318277 1981 314599 1982 309375 1983 304321 1984 300347 1985 298527 1986 300690 1987 306914 1988 314805 1989 324821 1990 336447 1991 350053 1992 367637 1993 387596 1994 406742 1995 423695 1996 437974 1997 448821 1998 455938 1999 460230 2000 464959 2001 471981 2002 478589 2003 483673 2004 486935 2005 486635 2006 482760 2007 475739 2008 465081 2009 452446 2010 440989 2011 434042 2012 434656 2013 442204 2014 453430 2015 465286 2016 476566 2017 487992 2018 500791 2019 514499 2020 523997 2021 528646 2022 536879 2023 551335