A change in the Treasurer or Secretary of the Treasury precipitates a series change, as these names feature prominently on currency.
For example, when Bush kicked Treasury Secretary Paul O'Neill out of the Cabinet (his signature is on Series 2001 bills) and replaced him with
John W. Snow, a new Series 2003 was introduced with Snow's signature. (The Treasurer, Rosario Amerin, stayed the same)
Also, Dorothy Elston, Treasurer alongside Secretary David Kennedy (Series 1969) married a Mr. Walter Kabis and then Kabis-Kennedy bills were then printed. (Series 1969A)
Also, a redesign of a bill precipitates a Series change. Example: When the new-style bills were introduced in the mid-90's, the Series on the newly redesigned denominations changed from 1995 to 1996, even though the signature combination was still Winthrow-Rubin.
| Series |
Treasurer |
Secretary of the Treasury |
1934,1934A (FRNs, $5 & $10 SCs)
1935,1935A ($1 SCs)
1928 B,C and D (USNs) |
William Julian
 |
Henry Morgenthau
 |
1934B (FRNs, $5 and $10 SCs)
1935B ($1 SCs)
1928E $2s, 1928D $5s |
William Julian
|
Fred Vinson
 |
1934C (FRNs, $5 and $10 SCs)
1935C ($1 SCs)
1928F $2s, 1928E $5s |
William Julian
|
John Snyder
 |
1934D (FRNs, $5 and $10 SCs)
1950 (FRNs)
1935D ($1 SCs)
1928G $2, 1928F $5 |
Georgia Clark
 |
John Snyder
|
1950A (FRNs)
1953 ($5 & $10 SCs, $2 & $5 USNs)
1935E ($1 SCs) |
Ivy Baker Priest
 |
George Humphrey
 |
1935F
$1 SCs |
Ivy Baker Priest
|
G. Humphrey
|
1935G
$1 SCs |
Elizabeth R. Smith
 |
C. Douglas Dillon
 |
1935H
$1 SCs |
Ivy Baker Priest
|
G. Humphrey
|
1953
$2 USNs / $5 and $10 Silver Certificates |
Ivy Baker Priest
|
G. Humphrey
|
1953A
$2 and $5 USNs / $5 and $10 Silver Certificates |
Ivy Baker Priest
|
Robert Anderson
 |
1953B
$2 and $5 USNs / $5 and $10 Silver Certificates |
Elizabeth R. Smith
|
C. Douglas Dillon
|
1953C
$2 and $5 USNs / $5 Silver Certificates |
Katherine O'Hay Granaham
 |
C. Douglas Dillon
|
1957
$1 Silver Certificates |
Ivy Baker Priest
|
Robert Anderson
|
1957A
Silver Certificates |
Elizabeth R. Smith
|
C. Douglas Dillon
|
1957B
Silver Certificates |
Katherine O'Hay Granaham
|
C. Douglas Dillon
|
1963
$1,$5,$10 and $20 FRNs ,$2 and $5 USNs |
Kathrine O'Hay Granaham
|
C. Douglas Dillon
|
1963A
$1 FRNs and $2 USNs only |
Kathrine O'Hay Granaham
|
Henry Fowler
 |
1963B
$1s only |
Kathrine O'Hay Granaham
|
Joseph W. Barr
 |
1966
$100 USNs only |
Kathrine O'Hay Granaham
|
Henry Fowler
|
1966A
$100 USNs only |
Dorothy Andrews Elston
 |
David M. Kennedy
 |
| 1969 |
Dorothy Andrews Elston
|
David M. Kennedy
|
| 1969A ($1s only) |
Dorothy Elston Kabis
 |
David M. Kennedy
|
| 1969B |
Dorothy Elston Kabis
|
John Connaly
 |
| 1969C and 1969D |
Romana Acosta Banuelos
 |
George P. Schultz
 |
| 1974 and 1976 (1976: $2s only) |
Francine Neff
 |
William Simon
 |
| 1977 |
Azie Taylor Morton
 |
W.H. Blumenthal
 |
| 1977A |
Azie Taylor Morton
|
G. William Miller
 |
| 1981 |
Angela M. Buchanan
 |
Daniel Regan
 |
| 1981A |
Katherine Savalos Ortega
 |
Daniel Regan
|
| 1985 |
Katherine Savalos Ortega
|
James A. Baker III
 |
| 1988 |
Katherine Savalos Ortega
|
Nicholas Brady
 |
| 1988A, 1990 |
Catherine Vilalpanto
 |
Nicholas Brady
|
| 1993 |
Mary Ellen Withrow
 |
Lloyd Bentsen
 |
| 1995, 1996 |
Mary Ellen Withrow
|
Robert E. Rubin
 |
| 1999 |
Mary Ellen Withrow
|
Lawrence H. Summers
 |
| 2001 |
Rosario Merin
 |
Paul O'Neill
 |
| 2003, 2004 |
Rosario Merin
|
John W. Snow
 |
| 2003A, 2004A |
Anna Cabral
 |
John W. Snow
|