Year Number 1970 82100 1971 73100 1972 63500 1973 86200 1974 73700 1975 108100 1976 119300 1977 121400 1978 131800 1979 140800 1980 159800 1981 154300 1982 141200 1983 148800 1984 187800 1985 200200 1986 197600 1987 201600 1988 213800 1989 217900 1990 212000 1991 205400 1992 206800 1993 176200 1994 225500 1995 194900 1996 191200 1997 278000 1998 276600 1999 264400 2000 262196 2001 253222 2002 195329 2003 187227 2004 194329 2005 206217 2006 224301 2007 230626 2008 220463 2009 218602 2010 327828.3336328915 2011 364230.3730300119 2012 391242.2470856096 2013 409973 2014 426688.4529493388 2015 466885 2016 468061 2017 482733 2018 496572.902011369 2019 523292.79000000004 2020 308450.215 2021 322356.79900000006