Four National Football League franchises parted ways with their head coaches on "Black Monday," with more firings and resignations seen coming. But some of those coaches delivered more bang for the buck than others.
Prominent exits include the New York Jets' Rex Ryan and the San Francisco 49ers' Jim Harbaugh. Aside from Harbaugh, whose departure was called a mutual agreement, the coaches mostly got the boot because of consistently underachieving squads.
Teams rarely disclose the financial terms of coaching contracts, and deals are often packed with bonuses, making exact salary figures difficult to determine.
However, evaluating the sum each coach earned this season per win—calculated from reported annual base salary estimates—offers a ballpark understanding of how wise of an investment the ex-coaches turned out to be.
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Reports and estimates of 2014 base salaries compiled by CNBC show most of the ex-coaches didn't give their franchises much bang for their buck. Calculating the coaches' base salary per team win, Ryan of the 4-12 Jets cost his team the most per win of the four departing coaches.
Harbaugh, whose 49ers slumped to an 8-8 record this season, proved the most efficient of the four coaches at about $625,000 per win. Mike Smith and Marc Trestman, whose Atlanta Falcons and Chicago Bears won six and five games, respectively, both cost their teams at least $750,000 per win.
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But the NFL's coaching casualties weren't necessarily the most expensive NFL coaches measured by salary per team win. Veteran coaches Tom Coughlin of the New York Giants, Jeff Fisher of the St. Louis Rams and Sean Payton of the New Orleans Saints all earned more than $1 million per win as their teams missed the playoffs.
Among playoff coaches, John Fox earned roughly $450,000 for each of the Denver Broncos' 12 wins, while Pete Carroll took in about $580,000 per victory for the 12-win Seahawks.
While team performance often drives personnel decisions, canning a coach can serve as more of a public relations action than a football move, said Andrew Zimbalist, a professor of economics at Smith College who has written extensively on sports. He noted that letting go of coaches can "send a message to the fan base" after a string of losing seasons.
"You want to give fans the sense that you'll turn the corner now," Zimbalist said.
Head coach salaries are "not irrelevant, but just a small factor" in actual hiring decisions, Zimbalist said. As the average franchise accumulates about $300 million in annual revenue, paying a coach $7 million rather than $4 million will rarely affect the process, he said.
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Franchises' relationships with fans and media can prove vital during transition periods, said John Challenger, CEO of job placement firm Challenger, Gray & Christmas. Teams, like businesses, often act quickly to expedite a "seamless" transition and show they're well-run organizations, he said.
"Like businesses, you have a vacuum at the top," Challenger said. "These teams are kind of directionless."
He added that similar to companies letting go of a CEO, teams firing a head coach or general manager might not eliminate all their problems. Incompetence at lower levels of the organization can persist through a change in top leadership—just as it can in corporate America.
Challenger noted that the Bears ditched both Trestman and general manager Phil Emery but have thus far kept quarterback Jay Cutler, who threw a league-high 18 interceptions while making a whopping $17.5 million.
Data also provided by 
