ISO
8601:2000(E)
©
ISO
2000
All
rights
reserved
25
Annex
A
(informative)
Relationship
to
ISO
2014,
2015,
2711,
3307
and
4031
In
preparing
the
first
edition
of
ISO
2014
an
examination
was
carried
out
of
the
potential
uses
of
all-numeric
dates.
The
advantages
of
the
descending
order
year-month-day
were
found
to
outweigh
those
for
the
ascending
order
day-month-year,
already
established
at
that
time
in
many
parts
of
the
world.
The
advantages
of
the
descending
order
were
found
to
include
the
following,
in
particular:
a)
the
avoidance
of
confusion
in
comparison
with
existing
national
conventions
using
different
systems
of
ascending
order;
b)
the
ease
with
which
the
whole
date
may
be
treated
as
a
single
numeral
for
the
purposes
of
filing
and
classification;
c)
arithmetic
calculation,
particularly
in
computer
uses;
d)
the
possibility
of
continuing
the
order
by
adding
digits
for
hour-minute-second.
For
times,
use
of
the
24-hour
timekeeping
system
is
how
so
common
(particularly
in
view
of
the
wide
availability
and
use
of
digital
watches)
that
separators
to
aid
human
interpretation
are
no
longer
necessary
but
are
included
as
options.
The
natural
addition
of
the
lower
order
time
digits
to
the
higher
order
date
digits
(see
above)
established
the
basic
concept
used,
in
the
preparation
of
this
International
Standard:
that
a
point
in
time
could
be
uniquely
represented
in
all-numeric
form
by
a
string
of
digits
commencing
with
year
and
ending
with
hour,
minute
or
second,
depending
on
the
precision
desired.
From
that
concept
representations
of
all
other
date
and
time
values
were
logically
derived
and,
thus,
ISO
2014,
ISO
3307
and
ISO
4031
have
been
superseded.
Numbering
of
days
and
weeks
in
the
year
based
on
the
Gregorian
calendar
is
important
in
many
commercial
applications.
Methods
of
numbering
the
weeks
of
the
year
vary
from
country
to
country,
and,
therefore,
for
international
trade
and
for
industrial
planning
within
international
companies
it
is
essential
to
use
uniform
numbering
of
weeks.
ISO
2015
and
ISO
2711
were
prepared
to
meet
these
requirements.
The
uniform
numbering
of
weeks
necessitates
a
unique
designation
of
the
day
on
which
a
week
begins.
For
commercial
purposes,
i.e.
accounting,
planning
and
similar
purposes
for
which
a
week
number
might
be
used,
Monday
has
been
found
the
most
appropriate
as
the
first
day
of
the
week.
Identification
of
a
particular
date
by
means
of
ordinal
dates
(ISO
2711)
and
by
means
of
the
week
numbering
system
(ISO
2015)
were
alternative
methods
that
the
basic
concept
of
this
International
Standard
could
also
encompass
and,
thus,
ISO
2015
and
ISO
2711
have
now
been
superseded.
