Year Number 1960 3319796 1961 3387611 1962 3466293 1963 3547889 1964 3630894 1965 3715890 1966 3802819 1967 3891537 1968 3982803 1969 4076791 1970 4174900 1971 4279120 1972 4392757 1973 4515990 1974 4647260 1975 4787769 1976 4935974 1977 5095881 1978 5269303 1979 5447917 1980 5583831 1981 5696104 1982 5825275 1983 5954343 1984 6078780 1985 6193326 1986 6296155 1987 6313609 1988 6305868 1989 6371681 1990 6479069 1991 6606891 1992 6733757 1993 6926213 1994 7274126 1995 7610238 1996 7850152 1997 8064784 1998 8255097 1999 8451625 2000 8655917 2001 8872203 2002 9100891 2003 9339183 2004 9586551 2005 9838645 2006 10094544 2007 10360896 2008 10636233 2009 10923458 2010 11236221 2011 11577539 2012 11941725 2013 12326038 2014 12722751 2015 13128327 2016 13561220 2017 14002439 2018 14426886 2019 14851787 2020 15293299 2021 15737224 2022 16176217 2023 16634672