There are plenty of differences between America's biggest companies but for some there is a common bond: CEOs with military backgrounds.
While it's not a requirement that a company leader have time in uniform, a working paper from the National Bureau of Economic Research showed it certainly doesn't hurt. CEOs with military backgrounds are fairly conservative with company financials and often outperform peers during stressful times, the paper found.
Unfortunately, the number of corporate CEOs with backgrounds in the military is shrinking, but here are 13 of the biggest names, along with what they did in the military.
1. Alex Gorsky
Currently: CEO of Johnson Johnson
Military experience: Graduated from West Point, then served six years in the U.S. Army and attained the rank of Captain. Ranger and Airborne qualified with service in Europe and Panama.
2. Lowell McAdam
Currently: CEO of Verizon
Military experience: Spent six years in the U.S. Navy's Civil Engineer Corps and attended Cornell on a Naval ROTC scholarship.
3. Bob Parsons
Currently: Founder and CEO of YAM Worldwide, Inc., and board member at GoDaddy, which he founded. He previously served as CEO of GoDaddy.
Military experience: Served as a U.S. Marine rifleman in Vietnam, where he was wounded by enemy fire while on patrol. He received the Combat Action Ribbon, Purple Heart, and Vietnamese Cross of Gallantry.
4. Fred Smith
Currently: Chairman, president, and CEO of FedEx Corporation
Military experience: Came up with the business model for Fedex will an undergrad at Yale, but took a break from school to enlist in the U.S. Marine Corps. He served two tours in Vietnam before he founded what would become FedEx in 1971.
5. Robert S. Morrison
Currently: Serves in board positions at Aon plc, 3M, and Illinois Tool Works Inc, among others. He previously served as the Vice Chairman at Pepsico, Inc., and the CEO of The Quaker Oats Company.
6. Daniel Akerson
Currently: Special advisor at the Carlyle Group. Akerson previously served as the chairman and CEO of General Motors from 2010 to 2014.
Military experience: Graduated from the U.S. Naval Academy in 1970 and served on the destroyer USS Dupont.
7. Robert McDonald
Currently: The Secretary of the U.S. Department of Veterans Affairs. He previously served as the CEO of Procter Gamble.
Military experience: A West Point graduate, McDonald served in the 82nd Airborne division and attained the rank of captain.
8. Scott Wine
Currently: Chairman and CEO of Polaris
Military experience: Graduated from the U.S. Naval Academy in 1989 and served in the Navy Supply Corps.
9. Stuart Parker
Currently: CEO of USAA
Military experience: Served in the U.S. Air Force for nearly ten years, flying combat missions during Operations Desert Shield and Desert Storm.
10. James Mulva
Currently: Sits on the board of directors at GE. He previously served as the president and CEO of ConocoPhillips.
Military experience: Graduated from Navy ROTC from The University of Texas in 1969 and served as a Navy officer until 1973.
11. Robert Stevens
Currently: Retired. Served as chairman, president, and CEO of Lockheed Martin, and later as Executive Chairman.
Military experience: Stevens enlisted in the U.S. Marine Corps in 1970, serving three years in III Marine Amphibious Force.
12. Jim Skinner
Currently: Chairman of Walgreens. Previously, he was the vice chairman and CEO of McDonalds.
Military experience: Over nearly ten years of service, completed two tours in the Gulf of Tonkin during the Vietnam War with the U.S. Navy.
13. Robert Myers
Currently: Chairman and CEO of Casey's General Stores, Inc.
Military experience: Enlisted in the U.S. Army in 1966, and served for 22 years, retiring as a lieutenant colonel. He served in Germany, Vietnam, Saudi Arabia, and Kuwait, according to Fortune.
SEE ALSO: 17 wild facts about the Vietnam War