With Times op-edster John Tierney's surprise announcement Tuesday that he'd be departing what is generally considered the most valuable real estate in American journalism — or at least used to be considered that, in the pre-Internet, pre-TimesSelect era — we were struck, as many no doubt were, by the brevity of his term. Tierney, who joined the page last year, replacing William Safire, was undoubtedly the shortest-serving current columnist. But, we wondered, was he perhaps the shortest-serving op-ed columnist ever? After some quality time with Nexis and the Times archive, we can now report that, yes, he was. After the jump, what we think is a complete list of all Times op-ed tenures since the page's inception in 1970.

John Tierney, April 2005–November 2006
Leslie H. Gelb, 1991–1993, 2 years
David Brooks, 2003–present, 3 years
Nicholas Kristoff, 2001–present, 5 years
Gail Collins, 1995–2001, 6 years
Paul Krugman, 1999–present, 7 years
C.L. Sulzberger, 1970–1977, 7 years
Flora Lewis, 1981–1990, 9 years
Frank Rich, 1994–2002, 2005–present, 9 years
Maureen Dowd, 1995–present, 11 years
Thomas L. Friedman, 1995–present, 11 years
Bob Herbert, 1993–present, 13 years
A.M. Rosenthal, 1986–1999, 13 years
James Reston, 1970–1989, 19 years
Tom Wicker, 1970–1991, 21 years
Russell Baker, 1970–1995, 25 years
Anthony Lewis, 1970–2001, 31 years
William Safire, 1973–2005, 32 years

— Jocelyn Guest