[ 1950 | 1951 | 1952 | 1953 | 1954
1955 | 1956 | 1957 | 1958 | 1959 ]
[ 1960 | 1961 | 1962 | 1963 | 1964
1965 | 1966 | 1967 | 1968 | 1969 ]
[ 1970 | 1971 | 1972 | 1973 | 1974
1975 | 1976 | 1977 | 1978 | 1979 ]
[ 1980 | 1981 | 1982 | 1983 | 1984
1985 | 1986 | 1987 | 1988 | 1989 ]
[ 1990 | 1991 | 1992 | 1993 | 1994
1995 | 1996 | 1997 | 1998 | 1999 ]
[ 2000 | 2001 | 2002 | 2003 | 2004
2005 | 2006 | 2007 ]
August 1950
Gulf States Utilities Company
Beaumont
February 1951
Central Power & Light Company
Corpus Christi
July 1951
Dallas Power & Light Company
Dallas
February 1952
Houston Lighting & Power
Houston
September 1952
City Public Service Board
San Antonio
February 1953
Southwestern Public Service Company
Amarillo
August 1953
Community Public Service Company
Possum Kingdom Lake
February 1954
Texas Power & Light Company
Dallas
August 1954
Southwestern Gas & Electric Company
Shreveport
February 1955
Texas Electric Service Company
Fort Worth
August 1955
Lower Colorado River Authority
Austin
February 1956
Dallas Power & Light Company
Beaumont
August 1956
Oklahoma Gas & Electric Company
Oklahoma City
February 1957
Gulf States Utilities Company
Beaumont
August 1957
Houston Power & Lighting Company
Houston
February 1958
Central Power & Light Company
Bayview
August 1958
City Public Service Company
San Antonio
February 1959
Southwestern Public Service Company
Amarillo
August 1959
Community Public Service Company
Possum Kingdom Lake
February 1960
Central Louisiana Electric Company
Alexandria
August 1960
Industrial Generating Company
Rockdale
February 1961
Texas Power & Light Company
Waco
August 1961
Southwestern Electric Power Company
Shreveport
February 1962
Texas Electric Service Company
Fort Worth
August 1962
Lower Colorado River Authority
Austin
February 1963
Dallas Power & Light Company
Dallas
August 1963
Gulf States Utilities Company
Beaumont
February 1964
Houston Power & Lighting Company
Houston
August 1964
Central Power & Light Company
Beaumont
February 1965
City Public Service Board
San Antonio
August 1965
El Paso Electric Company
El Paso
February 1966
Community Public Service Company
Fort Worth
August 1966
Oklahoma Gas & Electric Company
Oklahoma City
February 1967
Central Louisiana Electric Company
Alexandria
August 1967
Southwestern Public Service Company
Amarillo
February 1968
Industrial Generating Company
Salado
August 1968
Public Service Company of New Mexico
Albuquerque
February 1969
Texas Power & Light Company
Irving
August 1969
Southwestern Electric Power Company
Shreveport
February 1970
Lower Colorado River Authority
Austin
August 1970
Texas Electric Service Company
Wichita Falls
February 1971
Dallas Power & Light Company
Dallas
August 1971
Gulf States Utilities Company
Beaumont
February 1972
Central Power & Light Company
Corpus Christi
August 1972
Houston Lighting & Power Company
Houston
February 1973
City Public Service Board
San Antonio
August 1973
El Paso Electric Company
El Paso
February 1974
Community Public Service Company
Alexandria
August 1974
Oklahoma Gas & Electric Company
Oklahoma City
February 1975
Central Louisiana Electric Company
Alexandria
September 1975
Public Service Company of Oklahoma
Tulsa
February 1976
Texas Utilities Generating Company
Arlington
September 1976
Southwestern Public Service Company
Amarillo
February 1977
Industrial Generating Company (Rockdale)
Austin
September 1977
Public Service Company of New Mexico
Albuquerque
February 1978
Texas Power & Light Company
Irving
September 1978
Southwestern Electric Power Company
Shreveport
February 1979
Lower Colorado River Authority
Austin
September 1979
Texas Electric Service Company
Fort Worth
March 1980
Dallas Power & Light Company
Dallas
September 1980
Gulf States Utilities Company
Beaumont
March 1981
West Texas Utilities Company
Abilene
September 1981
Central Power & Light Company
Corpus Christi
March 1982
Houston Lighting & Power Company
Houston
September 1982
City Public Service Board
San Antonio
March 1983
El Paso Electric Company
El Paso
September 1983
Texas New Mexico Power Company
Fort Worth
March 1984
Oklahoma Gas & Electric Company
Oklahoma City
September 1984
Public Service Company of Oklahoma
Tulsa
March 1985
Texas Utilities Generating Company
Longview
September 1985
Texas Utilities Mining Company
Irving
March 1986
Southwestern Public Service Company
Amarillo
September 1986
Central Louisiana Electric Company
Alexandria
March 1987
Public Service Company of New Mexico
Albuquerque
September 1987
TU Electric
Waco
March 1988
Southwestern Electric Flower Company
Shreveport
September 1988
Lower Colorado River Authority
Austin
March 1989
Texas Utilities Electric Company
Fort Worth
September 1989
Gulf States Utilities Company
Beaumont
March 1990
City Public Service
San Antonio
September 1990
Central Power & Light Company
Corpus Christi
March 1991
Houston Lighting & Power Company
Houston
September 1991
West Texas Utilities Company
Abilene
March 1992
El Paso Electric Company
El Paso
September 1992
Texas New Mexico Power Company
Fort Worth
March 1993
Oklahoma Gas & Electric Company
Oklahoma City
September 1993
Public Service Company of Oklahoma
Tulsa
March 1994
TU Services / TU Electric
Dallas
September 1994
Southwestern Public Service Company
Amarillo
March 1995
Arizona Public Service Company
Phoenix
September 1995
Central Louisiana Electric Company
Alexandria
March 1996
Public Service Company of New Mexico
Albuquerque
September 1996
City of Austin
Austin
March 1997
Southwestern Electric Power Co.
Shreveport
September 1997
Lower Colorado River Authority
Austin
March 1998
City Public Service
San Antonio
September 1998
CSW
Corpus Christi
March 1999
Reliant Energy
Houston
September 1999
West Texas Utilities Company
Abilene
March 2000
Entergy
Beaumont
September 2000
El Paso Electric Company
El Paso
March 2001
Texas New Mexico Power Company
League City
September 2001
Oklahoma Gas & Electric Company
Oklahoma City
March 2002
Texas Utilities
Texas
September 2002
Tucson Electric Power
Tucson
March 2003
XCELL Energy
Denver, Colorado
September 2003
Arizon Public Service
Phoenix, Arizon
March 2004
Central Louisiana Electric
Alexandria, LA
September 2004
Public Service Co. of N.M.
Albuquerque, NM
March 2005
Austin Energy
Austin, TX
September 2005
Lower Colorado River
Austin, TX
March 2006
City Public Service
San Antonio, TX
September 2006
CenterPoint Energy
Galveston, TX
March 2007
American Electric Power
Shreveport, LA
September 2007
Entergy Corporation
Lake Charles, LA
March 2008
El Paso Electric
El Paso, TX
