Year of Birth

Yearly Rate of Increase

Monthly Rate of Increase

1930

4.5%

3/8 of 1%

1931-1932

5.0%

5/12 of 1%

1933-1934

5.5%

11/24 of 1%

1935-1936

6.0%

1/2 of 1%

1937-1938

6.5%

13/24 of 1%

1939-1940

7.0%

7/12 of 1%

1941-1942

7.5%

5/8 of 1%

1943 or later

8.0%

2/3 of 1%