Year Number 1960 162139 1961 171392 1962 177691 1963 183954 1964 191080 1965 198985 1966 206759 1967 214504 1968 222145 1969 229525 1970 235588 1971 240996 1972 248019 1973 255924 1974 264317 1975 272186 1976 278798 1977 285293 1978 291902 1979 298368 1980 300471 1981 296378 1982 289941 1983 282563 1984 280850 1985 285345 1986 291915 1987 300700 1988 309874 1989 317990 1990 324685 1991 329816 1992 334594 1993 340621 1994 347055 1995 353297 1996 359418 1997 365457 1998 370319 1999 374119 2000 376769 2001 379297 2002 382606 2003 386076 2004 390127 2005 394645 2006 399632 2007 404974 2008 410480 2009 416892 2010 422673 2011 428437 2012 437220 2013 448472 2014 460839 2015 474164 2016 489291 2017 505345 2018 520930 2019 536704 2020 552031 2021 563110 2022 551805 2023 548193