ISO 8601:2000(E)

8

© ISO 2000 ­ All rights reserved

and that the last calendar week of a calendar year is the week immediately preceding the first calendar week of the

next calendar year.

NOTE 1

These rules provide for a calendar year to have 52 or 53 calendar weeks;

NOTE 2

The first calendar week of a calendar year may include up to three days from the previous calendar year; the last

calendar week of a calendar year may include up to three days from the following calendar year;

NOTE 3

The time-interval formed by the week dates of a calendar year is not the same as the time-interval formed by the

calendar dates or ordinal dates for the same year. For instance:

- Sunday 1995 January 1 is the 7

th

day of the 52

nd

week of 1994, and

- Tuesday 1996 December 31 is the 2

nd

day of the 1

st

week 1997.

NOTE 4

The rule for determining the first calendar week is equivalent with the rule "the first calendar week is the week which

includes January 4".

4.3.2.3

Dates

Each calendar day can be identified by a calendar date, an ordinal date, or a week date.

A calendar date identifies a calendar day by

¾

its calendar year;

¾

its calendar month, and

¾

its ordinal number within its calendar month.

An ordinal date identifies a calendar day by

¾

its calendar year, and

¾

its ordinal number within the calendar year.

A week date identifies a calendar day by

¾

the calendar year to which its calendar week belongs;

¾

the calendar week number of its calendar week within that year, and

¾

its ordinal number within its calendar week.

4.4 Characters used in the representations

The representations specified in this International Standard use digits, alphabetic characters and special characters

specified in ISO/IEC 646. The particular use of these characters is explained in 4.5 and 5.1.

NOTE 1

Where the upper case characters are not available lower case characters may be used.

NOTE 2

Encoding of characters for the interchange of dates and times is not in the scope of this International Standard.

The space character shall not be used in the representations.