Chronology

The holdings record incorporates all levels of chronology data (e.g., year, month, day) (RECON: that are recorded consistently on the card.)

If both enumeration and chronology are present, ANSI states that both may be recorded. Yale records both. Note also that, per ANSI, if only enumeration is present, only enumeration is recorded; chronology is not supplied. And, vice versa, if only chronology is present, record only chronology; do not supply enumeration.

However, if a serial normally carries chronology data, and such data is omitted from a specific piece, it may be supplied within brackets. (ANSI option followed by Yale)

DATES (ANSI 5.5.5.2)

When more than one type of date is recorded, a single date is selected from the following preferred dates, in the order indicated:

Date of coverage

Date of publication

Date of copyright

Date of printing

The date of reprinting is not used in the holdings record because the chronology information used is that associated with the original work. Reprint information is properly a part of the bibliographic description of the work. 

The format for the year includes all four digits, even if the item does not.

1993/1994 not 1993/94

If the century or decade is not known, the year is not recorded.

Months, seasons, and days are recorded in the vernacular form appearing on the publication and romanized, if necessary. Chronology data is abbreviated according to the appropriate portions of AACR 2 Appendix B.

http://www.library.yale.edu/cataloging/abbrev.htm

Day notations are not treated as a separate hierarchical level.

USE: (1968:June 12)
NOT: (1968:June:12)

Chronology data is recorded from highest hierarchical level to lowest; the colon is used to separate each level:

(1980:Jan.)
(1996:Oct.19:am) <daily newspaper w/morning & evening eds.>

Note that a blank space is used in chronology data to separate a month from a day if the month is not abbreviated. (See Section 7. Punctuation)

Use a forward slash if the chronology spans a non-calendar year or more than one year:

1989/1990 <either a non-calendar year or a biennial>
1990/1992 <triennial>

YUL practice: Although ANSI standard is to record non-Gregorian chronological data when it is the only scheme used, YUL East Asia and Near East teams convert the chronological data to Gregorian; dates are not bracketed; months and seasons are translated into English.

East Asia example:

245 0 0 ‡6 880-01 ‡a Wen xue Taiwan.
310     Quarterly
362 0   ‡6 880-04 ‡a no. 1(2002 chun ji)-
866 4 1 ‡8 0 ‡a no.1(2002:spring)-no.3(2002:fall)

Hebraica: If only the non-Gregorian date appears on the source, Hebraica records the non-Gregorian date followed by the Gregorian year in brackets; Gregorian months and seasons are not recorded. If both the non-Gregorian and Gregorian dates appear on the source, only the Gregorian date (including transliterated months and seasons) is recorded.

Hebraica example (Gregorian date does not appear on the source):

245 0 0 ‡a BDD : ‡b be-khol derakhekha daʻehu : ketav-ʻet le-ʻinyene Torah u-madaʻ.
362 0   ‡a Ḥov. 1 (755 [1994 or 1995])-
866 4 1 ‡8 0 ‡a ḥov.1(755 [1994 or 1995])

NOTE: The earlier Gregorian date is recorded in the item record CHRON field to facilitate shelving; the non-Gregorian date is not recorded in CHRON.

Hebraica example (Gregorian date appears on the source):

245 0 0 ‡a ʻEmdah : ‡b biṭaʾon le-sifrut.
362 0   ‡a 1 (aviv 1995)-
866 4 1 ‡8 0 ‡a 4(1996:ḥoref)-10(2002:kayits)
Effective Date: 
February 4, 2014