651 Social security
1947	3,301
1948	3,613
1949	4,133
1950	4,974
1951	9,449
1952	11,980
1953	15,453
1954	18,907
1955	24,728
1956	29,786
1957	34,900
1958	41,781
1959	48,694
1960	57,498
1961	60,829
1962	69,268
1963	75,179
1964	78,238
1965	80,747
1966	93,736
1967	88,399
1968	113,459
1969	108,544
1970	114,065
1971	130,100
1972	139,077
1973	165,135
1974	174,599
1975	187,521
1976	195,225
1977	209,012
1978	215,845
1979	221,363
1980	231,568
1981	248,556
1982	259,552
1983	272,148
1984	273,998
1985	280,714
1986	288,839
1987	293,265
1988	300,392
1989	306,682
1990	316,001
1991	329,107
1992	342,851
1993	354,652
1994	364,223
1995	374,658
1996	382,441
1997	391,841
1998	401,159
1999	407,283
2000	418,896
2001	433,129