Here is the complete story about 300 year old people on the Social Security Databases. Grace M. Hopper is the key.

[Celerity]

8. Not 300 year olds, it was 150 year olds. Here is why:

The US Social Security computer system runs on the old COBOL programming language, which does not use a date or time type.

So the date is stored as a number using the ISO 8601 standard. The origin for this is 150 years ago, the 1875 Metre Convention's date.

So if you don’t know the date of something, it will be a 0 value, which in COBOL will default to 1875, ie 150 years ago, the date of the Convention du Mètre.



https://en.wikipedia.org/wiki/Metre_Convention

The Metre Convention (French: Convention du Mètre), also known as the Treaty of the Metre, is an international treaty that was signed in Paris on 20 May 1875 by representatives of 17 nations: Argentina, Austria-Hungary, Belgium, Brazil, Denmark, France, Germany, Italy, Peru, Portugal, Russia, Spain, Sweden and Norway, Switzerland, Ottoman Empire, United States of America, and Venezuela.

The treaty created the International Bureau of Weights and Measures (BIPM), an intergovernmental organization, under the authority of the General Conference on Weights and Measures (CGPM) and the supervision of the International Committee for Weights and Measures (CIPM). These organizations coordinate international metrology and the development of internationally recognized systems of measurement.