Marshall Date Codes

Code	Year
A	1969–70
C	1971
D	1972
E	1973
F	1974
G	1975
H	1976
J	1977
K	1978
L	1979
M	1980

Code	Year
N	1981
P	1982
R	1983
S	1984
T	1985
U	1986
V	1987
W	1988
X	1989
Y	1990
Z	1991–92

Celestion Date Codes

Month
M
A	Jan
B	Feb
C	Mar
D	Apr
E	May
F	Jun
G	Jul
H	Aug
I/J	Sep
K	Oct
L	Nov
M	Dec

1944–1955
DDMY
A	1944
B	1945
C	1946
D	1947
E	1948
F	1949
G	1950
H	1951
I/J	1952
K	1953
L	1954
M	1955

1956–1968
DDMY
A	1956
B	1957
C	1958
D	1959
E	1960
F	1961
G	1962
H	1963
I/J	1964
K	1965
L	1966
M	1967
A	1968

1969–1991
MYDD
B	1969
C	1970
D	1971
E	1972
F	1973
G	1974
H	1975
I/J	1976
K	1977
L	1978
M	1979
N	1980
P	1981
Q	1982
R	1983
S	1984
T	1985
U	1986
V	1987
W	1988
X	1989
Y	1990
Z	1991

1991–2014
DDMY
A	1991
B	1992
C	1993
D	1994
E	1995
F	1996
G	1997
H	1998
I/J	1999
K	2000
L	2001
M	2002
N	2003
P	2004
Q	2005
R	2006
S	2007
T	2008
U	2009
V	2010
W	2011
X	2012
Y	2013
Z	2014

2015–Date
MYDD
A	2015
B	2016
C	2017
D	2018
E	2019
F	2020
G	2021
H	2022
I/J	2023
K	2024
L	2025
M	2026
N	2027