In 2018, more CEOs were ousted due to ethical lapses than company financial performance or struggles with a company's board, according to a new study from PwC's Strategy&. It is the first time in its 19-year history that the study has found the majority of CEOs were dismissed because of ethical issues.

For its annual CEO Success study, Strategy& (the consulting arm of PwC) analyzes the world's largest 2,500 public companies, defined by their market cap on Jan. 1. The study defines CEO dismissals due to ethical lapses as "the removal of the CEO as the result of a scandal or improper conduct by the CEO or other employees; examples include fraud, bribery, insider trading, environmental disasters, inflated resumes, and sexual indiscretions."

The Washington Post reports that 39% of CEO oustings in 2018 were due to ethical lapses (including Les Moonves at CBS), 35% were due to financial performance and 13% were the result of conflicts with the company's board.

That breakdown is very different than previous findings. For example, as the Post points out, at the height of the crisis in 2008, 52% of CEO dismissals were due to financial performance, 35% were due to board conflicts and 10% were due to misconduct.

"The rise in these kinds of dismissals reflects several societal and governance trends, including more aggressive intervention by regulatory and law enforcement authorities, new pressures for accountability about sexual harassment and sexual assault brought about by the rise of the 'Me Too' movement, and the increasing propensity of boards of directors to adopt a zero-tolerance stance toward executive misconduct," the study states.

The number of forced turnovers for CEOs in 2018 overall, the study found, was in-line with long-term trends, at 20%. Additionally, the study found that the share of incoming women CEOs in 2018 was 4.9%, slightly lower than 2017's all-time high of 6%.

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