White House Chief of Staff Tenure, Reagan-Trump (as of May 15, 2020)

POTUS	Chief of Staff	Start	Finish	Days
Reagan 40	James A. Baker III	1/20/1981	2/4/1985	1476
	Donald T. Regan	2/4/1985	3/2/1987	756
	Howard H. Baker, Jr.	3/2/1987	7/1/1988	487
	Kenneth M. Duberstein	7/1/1988	1/20/1989	203
Bush 41	John H. Sununu	1/20/1989	12/6/1991	1050
	Samuel K. Skinner	12/6/1991	8/14/1992	252
	James A. Baker III	8/14/1992	1/20/1993	159
Clinton 42	Thomas F. McLarty III	1/20/1993	6/28/1994	524
	Leon E. Panetta	6/28/1994	1/17/1997	934
	Erskine B. Bowles	1/17/1997	10/21/1998	642
	John D. Podesta	10/21/1998	1/20/2001	822
Bush 43	Andrew H. Card, Jr.	1/20/2001	4/14/2006	1910
	Joshua B. Bolten	4/14/2006	1/20/2009	1012
Obama 44	Rahm I. Emanuel	1/20/2009	10/1/2010	619
	William M. Daley	1/13/2011	1/27/2012	379
	Jacob J. Lew	1/27/2012	1/25/2013	364
	Denis R. McDonough	1/25/2013	1/20/2017	1456
Trump 45	Renhold R. "Reince" Priebus	1/20/2017	7/31/2017	192
	John F. Kelly	7/31/2017	1/2/2019	520
	John "Mick" Mulvaney	1/2/2019	3/31/2020	454
	Mark R. Meadows	3/31/2020	present

COS TENURE	AVG
RR-DT COS AVG TENURE:	711
REAGAN 40 COS AVG TENURE:	731
BUSH 41 COS AVG TENURE:	487
CLINTON 42 COS AVG TENURE:	731
BUSH 43 COS AVG TENURE:	1461
OBAMA 44 COS AVG TENURE:	705
TRUMP 45 COS AVG TENURE:	389