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 0 1986 0 1987 0 1988 0 1989 0 1990 0 1991 0 1992 0 1993 0 1994 0 1995 14 1996 920 1997 2200 1998 7000 1999 18000 2000 139000 2001 225000 2002 338225 2003 475942 2004 787000 2005 1089800 2006 1358152 2007 1882830 2008 2423416 2009 2136409 2010 2550592 2011 3217261 2012 3584283 2013 3696834 2014 3738125 2015 3713137 2016 3788490 2017 3746644 2018 3636931 2019 3613846 2020 3420383 2021 3900179 2022 4170329