Year Number 1961 9210332 1962 9551528 1963 9914656 1964 10275019 1965 10594894 1966 11575352 1967 11829246 1968 12080061.52 1969 12341753.120000001 1970 12468822.719999999 1971 12673714.08 1972 12848676.08 1973 13074282.879999999 1974 13443742.04 1975 13456593.48 1976 13710593.32 1977 14010768.32 1978 14282683 1979 14420508 1980 14899564 1981 14989080 1982 15263777 1983 15476147 1984 15670531 1985 16077802 1986 16286542 1987 16464924 1988 16437959 1989 16514949 1990 16023315 1991 15763511 1992 15808750 1993 15993708 1994 16162178 1995 16252435 1996 16242202 1997 16248526 1998 16299306 1999 16335577 2000 16317861.5 2001 15428452 2002 15585456 2003 13737793 2004 13663311