C.7. Alternative Dates

When giving alternative dates of birth or death in headings for persons, apply the following:

1. If the dates are the last year of one century and the first year of the following century, give the complete date for both (e.g., 1899 or 1900).

2. If the dates are the first and second years of the same century, give the complete date for both (e.g., 1900 or 1901).

3. If the dates are the last year of one decade and the first year of the following decade in the same century, give the complete date for the first and the last two digits of the second date (e.g., 1979 or 80).

4. If the dates are any two years within the second decade of the same century, give the complete date for the first and the last two digits of the second date (e.g., 1914 or 15).

5. If the dates are the first two years of a decade (other than the first two years of the first decade of the century), give the complete date for the first and the last two digits of the second date (e.g., 1970 or 71).

6. If the dates are those not covered by 1. - 5. above, give the complete date for the first and the final digit of the second date (e.g., 1978 or 9).