| Russell Felter | January 1, 1999 - December 31, 2018 |
| Evelyn Brown | January 1, 1995 - December 31, 1998 |
| Frances Slayton | January 1, 1987 - December 31, 1994 |
| Horace Chamberlain | January 1, 1975 - December 31, 1986 |
| Ralph Atkinson | January 1, 1971 - December 31, 1974 |
| Arthur Mitchko | January 1, 1967 - December 31, 1970 |
| Samuel P. Sutphen | January 1, 1963 - December 31, 1966 |
| Everitt Rhinehart | January 1, 1959 - December 31, 1962 |
| Ray Burkett | January 1, 1957 - December 31, 1959 |
| Wilbur S. Willis | January 1, 1955 - December 31, 1956 |
