On the issue of "century" then, would it be reasonable to strike the word "century" from the spec altogether? 


Or alternatively, include a note to the effect that "This spec does not define century because there does not seem to be any internationally agreed-upon definition."


And further, that:


" '19' means the period covering the years 1901 through 1999.  And this is intended to be consistent with ISO 8601, although it is not clear from that standard precisely what '19' is intended to mean".


This, of course, would mean that none of the stakeholders in this process has the need for "century" support, to any degree that cannot be satisfied by the above.





From: Discussion of the Developing Date/Time Standards [mailto:[log in to unmask]] On Behalf Of Simon Grant
Sent: Tuesday, December 21, 2010 4:33 PM
To: [log in to unmask]
Subject: Re: [DATETIME] century


I agree with Gerard, and yes, that means "19" would mean 1900 through to 1999.

I don't think it is necessary to reconcile that with any common definition of century, as the two concepts are independent. If people want to define the 20th century, that's fine by me, if they all agree...



On 21 December 2010 20:47, Ray Denenberg, Library of Congress <[log in to unmask]> wrote:

So you would interpret '19' to mean 1900 through 1999.  I don't disagree with you, but how do you reconcile this with the fact that the contemporary definition of "20th century" is 1901 through 2000 (and 8601 does say that '19' means a "century" even if it doesn't say which one)?


If we were to adopt this interpretation, then the question becomes, is there a need to (separately) represent "20th century" according to the contemporary definition, and if so how do we want to do that.






From: Gerard Ashton [mailto:[log in to unmask]]
Sent: Tuesday, December 21, 2010 3:25 PM
To: Discussion of the Developing Date/Time Standards
Cc: Denenberg, Ray
Subject: Re: century


Whatever name we give to the year numbering system used in ISO-8601, be it Anno Domini, Common Era, or something else, it is based on the opinion of Dionysius Exiguus as to the date of the incarnation of Jesus of Nazareth. Unfortunately the surviving documents written by Dionysius are anything but clear about the exact date the era begins. Blackburn & Holford-Strevens present arguments for 2 BC, 1 BC, or AD 1 as the year of the origin of the dating system, and the date within the year is also up for grabs. I would say that when one is not using IS0 8601, it is impossible to determine exactly which years are included in the 20th century. In an ISO 8601 context, I would interpret the date 19 to mean the all dates where the thousands digit of the year is 1 and the hundreds digit of the year is 9.

Blackburn, Bonnie; Leofranc Holford-Strevens (2003). The Oxford companion to the Year: An exploration of calendar customs and time-reckoning. Oxford University Press. p. 778-9.

On 12/21/2010 2:37 PM, Denenberg, Ray wrote:

.  According to ISO 8601 '19' means the century.  
Two problems:
1. What century?
2. What is a century? 


Simon Grant
+44 7710031657