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CEO pay keeps rising

The nation's chief executive officers received pay raises of about 4.5 percent in 2015, a study by the data firm Equilar, which released on Wednesday, found.

The median pay for a U.S. CEO was $468,449, but most on the Standard & Poor's 500 Index earned compensation of about $10.8 million, a $500,000 increase over 2014, the study determined.

The nation's highest-paid CEO was tech head Dara Khosrowshahi of Expedia, who earned $94.6 million. His pay came mostly from stock options tied to an incentive plan that would require him to push shares to a $170-average-share benchmark by 2020, a provision in his five-and-a-half-year compensation arrangement, according to the study, which was completed on behalf of The Associated Press and which reviewed pay for 341 corporate heads.

Many CEOs are paid based on performance and are rewarded with stock options rather than simply cash payouts, it noted. However, a review of data from 1994 to 2011, found that salaries of higher paid CEOs did not keep pace with corporate returns, the study said.

In the Equilar study, some CEOs saw large increases in pay over the last year, including Sandeep Mathrani of General Growth Properties, whose earnings rose 702 percent to $32.9 million. Sean M. Healey, the CEO of Affiliated Managers Group, saw an increase of 226 percent, earning $17.5 million.

By contrast, Richard A. Hayne, CEO of Urban Outfitters, saw a 92 percent salary reduction to $4.4 million, while Hock E. Tan, CEO of Broadcom, saw a 77-percent dip, earning $4 million. Pay for Montgomery F. Moran, CEO of Chipotle Mexican Grill, dropped 52 percent to $13.6 million.

Of the 341 CEOs in the survey, just 17 are women. Of that group, though, 10 ranked in the top 100 CEO salaries overall. In fact, for the second year in a row, women who do reach CEO ranks are earning more, on average – a median pay of $18 million annually, for a 13-percent jump from 2014 – than their male counterparts.

Top female CEO pay went to Yahoo's Marissa Mayer, who earned about $36 million, a dip of 15 percent, followed by PepsiCo Inc. CEO Indra Nooyi, who received $22.2 in 2015. Phoebe Nvakovic, who heads General Dynamics, earned the third spot with $22.2 million in pay.

The nation's longest-serving female CEO is Debra Cafaro of Ventas, Inc., who has helmed her company for 17 years. She is the daughter of a Pittsburgh mailman and earned $10.9 million last year, putting her at No. 314 on the 2015 compensation list with a 9-percent raise in earnings.

Still, other analysts note that outside of the top ranks, women CEOs don't do as well. Noted Pavle Sabic, who authored a study about CEO pay for S&P Global Market Intelligence: "The gender gap at the CEO level … is not closing."

His research found that the "growth rate for new female CEOs is only one per year, every two years." Of the S&P's 500 companies, Information Technology hires the most female CEOs, while "energy, materials and telecoms have no female CEOs," he wrote.

He added of his research: "Things may not change any time soon. At the end of 2014, the S&P 500 Index had 25 female CEOs. Latest figures show this number has declined to 22 female CEOs."