Year Number 1960 20678 1961 21312 1962 21924 1963 22529 1964 23135 1965 23758 1966 24395 1967 25039 1968 25688 1969 26340 1970 26992 1971 27577 1972 28297 1973 28756 1974 29279 1975 29957 1976 30559 1977 31156 1978 31285 1979 31532 1980 31795 1981 32150 1982 32302 1983 32226 1984 32379 1985 32603 1986 32767 1987 34145 1988 34286 1989 34547 1990 34757 1991 35264 1992 35454 1993 36218 1994 37170 1995 37627 1996 38070 1997 38592 1998 39504 1999 40348 2000 40792 2001 40908 2002 42238 2003 41848 2004 41811 2005 42114 2006 43110 2007 43445 2008 44554 2009 44861 2010 46283 2011 45246 2012 45851 2013 46847 2014 47687 2015 48844 2016 49579 2017 50266 2018 50828 2019 51368 2020 51864 2021 52299 2022 63113 2023 62940