Year Number 1970 511400 1971 582100 1972 706600 1973 830900 1974 840800 1975 912100 1976 1060800 1977 1136600 1978 1238900 1979 1301600 1980 1284500 1981 1358100 1982 1447600 1983 1498400 1984 1514000 1985 1708000 1986 1640400 1987 1879700 1988 1964600 1989 2283800 1990 2532100 1991 2605700 1992 3024200 1993 3296900 1994 3747900 1995 4265400 1996 4718600 1997 5153900 1998 5871500 1999 6056600 2000 6641875 2001 6550376 2002 7070344 2003 6902780 2004 7619372 2005 8037890 2006 8785116 2007 9140909 2008 9140680 2009 8520740 2010 13493793 2011 14088251.6640568 2012 14518841.0529716 2013 15037454 2014 15210489 2015 14718641 2016 14724774 2017 16171640 2018 12935505 2019 46476602 2020 13285414 2021 18901048