Year Number 1960 0 1965 0 1970 0 1975 0 1976 0 1977 0 1978 0 1979 0 1980 0 1981 0 1982 0 1983 0 1984 0 1985 300 1986 1500 1987 3475 1988 6300 1989 13579 1990 25000 1991 32000 1992 44000 1993 61100 1994 88000 1995 158000 1996 288600 1997 545000 1998 946000 1999 1677000 2000 2461000 2001 2970000 2002 3000000 2003 3500000 2004 3860000 2005 4270000 2006 4690135 2007 4970719 2008 5048127 2009 4704497 2010 4701474 2011 4906352 2012 5013676 2013 4880792 2014 4912620 2015 4902009 2016 4875116 2017 4898872 2018 4971493 2019 5160309 2020 5234009 2021 5373865 2022 5690017