Year Number 1971 248908 1972 259757 1973 271074 1974 278609 1975 282793 1976 285786 1977 280315 1978 275564 1979 275020 1980 270346 1982 250510 1983 245000 1984 243000 1985 244000 1987 213000 1988 215000 1989 225000 1990 228000 1991 229100 1992 230200 1999 249384 2000 248148 2001 261362 2002 264111 2003 262390 2004 258966 2005 265257 2006 249862 2007 255690 2008 244391 2009 245879 2010 252290 2011 255994 2012 247079 2013 250692.984375 2014 272430 2016 313648.9375 2017 318533.15625 2018 279097.09375 2019 280504.6875 2020 281265.78125 2021 285964.65625