Year Number 1964 55492 1965 55432 1966 55432 1967 55428 1968 55436 1969 55372 1970 55247 1971 55242 1972 55232 1973 55216 1974 55158 1975 55043 1976 54854 1977 54611 1978 54367 1979 54238 1980 54082 1981 53757 1982 53251 1983 52589 1984 52061 1985 51580 1986 51136 1987 50602 1988 50109 1989 49685 1990 49182 1991 49253 1992 49545 1993 49587 1994 49822 1995 49801 1996 49783 1997 50162 1998 50680 1999 51451 2000 52127 2001 52517 2002 52910 2003 53291 2004 53819 2005 54366 2006 54594 2007 54611 2008 54721 2009 54930 2010 55199 2011 55402 2012 55559 2013 55348 2014 55104 2015 55080 2016 55031 2017 55047 2018 55070 2019 54940 2020 54889 2021 54884 2022 54876