Year Number 1970 363518 1971 357936 1972 354748 1973 345284 1974 337816 1975 328401 1976 316265 1977 306349 1978 297102 1979 290859 1980 291722 1981 285179 1982 286780 1983 290800 1984 288623 1985 278060 1986 268820 1987 261603 1988 259270 1989 257833 1990 257932 1991 260286 1992 262599 1993 261534 1994 251097 1995 261648 1996 269668 2007 301101 2008 299704 2009 294602 2010 263906 2011 258293 2012 252735 2013 244045 2014 241676 2015 239095 2016 236943 2017 234653 2018 233553 2019 234947 2020 232810 2021 234240