NEW YORK (TheStreet) -- Less than 5% of companies in the S&P 500 are run by women, surprising, given the strides women seem to have made reaching the upper echelons of leadership at large companies.

More shocking is that the majority of these 23 women CEOs have had the top position at their respective company for five years or less. One of the few exceptions -- and the longest-tenured woman CEO at an S&P 500 company -- is Debra Cafaro, the CEO of Ventas Inc. (VTR - Get Report) . She has been in the position since 1999 and has helped her company grow from a $200 million concern to a $22 billion juggernaut over that time.

These CEOs were put in the spotlight this week when Dealbook's Andrew Ross Sorkin pointed out that activist investors may prefer to target companies with women CEOs.

Meet the 23 women who are CEOs of S&P 500 companies. The list is sorted by market cap, from smallest to largest.

23. Sheri S. McCoy
Avon Products (AVP - Get Report)
Market Cap: $3.7 billion
Became CEO in 2012
Age: 56
2013 Compensation: $10.2 million

Prior to being appointed as Avon's chief executive, Sheri McCoy spent 30 years at Johnson & Johnson (JNJ) . In her last position there, McCoy was Vice Chairman of the Executive Committee, where she was responsible for the pharmaceutical and consumer business segments, which represent more than 60% of the company's revenue.

22. Gracia C. Martore
Gannett Co. (GCI - Get Report)

Market Cap: $7.84 billion
Became CEO in 2011
Age: 63
2013 Compensation: $7.9 million

Gracia Martore is a longtime Gannett employee. She started at the media company back in 1985 as assistant treasurer. Martore worked her way up through company finance and investor relations roles and has been Gannett's chief financial and chief operating officer throughout her tenure there. She was named CEO on Oct. 6, 2011.

Martore has been named one of Fortune magazine's "50 Most Powerful Women in Business" in 2012. As Gannett's financial chief, she was named the Best CFO in America in the publishing and advertising business for three years, from 2004 to 2006.


21. Maggie Wilderotter
Frontier Communications Corp. (FTR - Get Report)

Market Cap: $8.33 billion
Became CEO in 2004
Age: 60
2013 Compensation: $6.6 million

Maggie Wilderotter joined Frontier in November 2004 as CEO and was named Chairman and CEO in 2006. Prior to Frontier, Wilderotter was a senior vice president at Microsoft (MSFT) . Previously, after holding executive positions at AT&T (T) , Wilderotter was CEO of Wink Communications. 


20. Beth E. Mooney
KeyCorp (KEY - Get Report)
Market Cap: $12.2 billion
Became CEO in 2011
Age: 60
2013 Compensation: $7.5 million

Beth Mooney was named CEO and chairman in May 2011. She has more than 30 years of experience in the retail banking, commercial lending and real estate financing industries and has been at KeyCorp since 2006. Before that she was the chief financial officer at AmSouth Bancorp (now a part of Regions Financial (RF) ).

Mooney has been recognized by both Forbes and Fortune Magazine in their powerful women in business rankings.


19. Denise M. Morrison
Campbell Soup Co. (CPB - Get Report)
Market Cap: $14.99 billion
Became CEO in 2011
Age: 61
Fiscal 2014 Compensation: $9.7 million

Denise Morrison became Campbell Soup's chief executive in August 2011, after more than eight years at the packaged food company and more than 30 in the food business. Before Campbell Soup, Morrison was in charge of Kraft Foods' (now a part of Mondelez International (MDLZ - Get Report) ) snacks and confections divisions. Other companies on her resume include Nabisco, Nestle and PepsiCo (PEP - Get Report) and Procter & Gamble (PG) .

Morrison also a founding member of Healthy Weight Commitment Foundation, an initiative of manufacturers and retailers to combat obesity in the marketplace, workplace, and schools. Named to President Barack Obama's Export Council in 2012, she is regularly named among the Fortune and Forbes most powerful women.


18. Ursula M. Burns
Xerox Corp. (XRX - Get Report)

Market Cap: $15.2 billion
Became CEO in 2009
Age: 56
2013 Compensation: $10.2 million (including stock awards given on Jan. 1, 2014)

Ursula Burns, chairman and CEO of Xerox, is the first African American woman to head a Fortune 500 corporation. She is a longtime Xerox employee, joining the company in 1980 as a mechanical engineering summer intern. Shortly after her appointment as chief executive in July 2009, she made the company's largest acquisition to date -- the $6.4 billion purchase of Affiliated Computer Services. She became Xerox's chairman in 2010.

 

17. Lauralee E. Martin
HCP Inc. (HCP - Get Report)

Market Cap: $19.61 billion
Became CEO in 2013
Age: 64 (approximate)
2013 Compensation: $8.4 million

Lauralee Martin joined HCP, a health care real estate investment trust in October 2013. Before that she was the CEO of Jones Lang LaSalle (JLL) , a real estate services and money management firm. She joined Jones Lang LaSalle as its chief financial officer in 2002.

Martin has more than 20 years of experience in key operational and finance roles within the real estate industry.

 

 

 

16. Barbara Rentler
Ross Stores (ROST - Get Report)
Market Cap: $19.82 billion
Became CEO in 2014
Age: 57
2013 Compensation: $4.8 million (for her former position as chief merchandising officer)

Barbara Rentler became CEO of Ross Stores in June 2014 as part of the discount retail chain's succession plan in which its longtime CEO and Vice Chairman Michael Balmuth became Executive Chairman. Rentler has been with Ross Stores since 1986, rising up through the company's various divisions. Prior to becoming its chief executive, she was president and chief merchandising officer for Ross Dress for Less, its main off-price apparel and home fashion chain.

15. Heather Bresch
Mylan Inc. (MYL - Get Report)
Market Cap: $20.28 billion
Became CEO in 2012
Age: 45
2013 Compensation: $8.7 million

Over her 20-year career at generic drug maker Mylan, the company says on her official profile page that CEO Heather Bresch is passionate about giving HIV/AIDS patients access to treatment, advocating for patients, and providing access to lower-cost versions of life-saving products. Bresch is also a proponent of increasing food allergies awareness and advocating for one quality standard for all drugs sold in the U.S.

Mylan is acquiring Abbott Laboratories' (ABT)  specialty and branded generics business in developed markets outside the U.S. The transaction is expected to be completed this quarter.

 

14. Debra A. Cafaro
Ventas Inc. (VTR - Get Report)
Market Cap: $22.5 billion
Became CEO in 1999
Age: 57
2013 Compensation: $9.1 million

Debra Cafaro has been the real estate investment trust's chief executive since 1999 and its chairman since 2003. Under her leadership, Ventas' market cap has risen from $200 million to roughly $22 billion. And in the 15-year period ending Dec. 31, Ventas' compound annual total shareholder return was 29%.

According to her company biography, Cafaro was recognized in 2014 by the Harvard Business Review in its list of "The Best-Performing CEOs in the World," ranking her in the top 30 global CEOs. Last year, TheStreet's Jim Cramer named Cafaro as one of the "Bankable 21" CEOs.

13. Debra L. Reed
Sempra Energy Corp. (SRE - Get Report)

Market Cap: $26.3 billion
Became CEO in 2011
Age: 58
2013 Compensation: $9.8 million

Debra Reed has been CEO of Sempra Energy since 2011 and its chairman since 2012 as well as a longtime employee. Prior to leading the San Diego-based energy services company, Reed was president and CEO of San Diego Gas & Electric Co. and Southern California Gas Company, Sempra Energy's regulated California utilities. She also serves on the Board of Directors of Halliburton (HAL) .

Reed joined SoCalGas in 1978 and became the company's first female officer 10 years later. From 2011 to 2014, she has been recognized by Fortune magazine's "50 Most Powerful Women in Business." Last year she was appointed by the U.S. Secretary of Energy to the National Petroleum Council.

 

12. Susan M. Cameron
Reynolds American (RAI)

Market Cap: $38.1 billion
Became CEO in 2014
Age: 56
2013 Compensation: N/A (Cameron was in retirement in 2013. Her new contract reportedly is for $1.3 million annual salary with a $500,000 signing bonus. In 2010, her last full year as CEO before her first retirement, her total compensation was $23.8 million.)

Susan Cameron came out of retirement to retake the position CEO at Reynolds American in May 2014, succeeding Daniel Delen. Delen had held the position since 2011, when Cameron stepped down as the company's chairman and CEO.

Cameron was back in position in time to lead the cigarette maker as it announced a $27.4 billion deal to buy Lorillard. The acquisition is the largest ever by a woman CEO. It is expected to be completed mid-2015, pending regulatory approval. 

Cameron joined an early predecessor to Reynolds American in 1981 as a sales representative and held numerous international and domestic marketing roles during her tenure. She is also active in women's leadership initiatives has been recognized by Forbes magazine, FORTUNE magazine and the Financial Times as one of the most powerful women in business.


11. Marissa Mayer
Yahoo! (YHOO)
Market Cap: $41.3 billion
Became CEO in 2012
Age: 39
2013 Compensation: $24.9 million

Marissa Mayer was named Yahoo! president and CEO in July 2012. After 13 years at Google (GOOGL) , serving in a variety of product, engineering, design and executive positions, Mayer's move to Yahoo! was much-discussed. In her most recent position at Google, she oversaw product management, engineering, design and strategy for the company's suite of local and geographical products, including Google Maps, Google Earth, Zagat, Street View, as well as local search for desktop and mobile. Mayer also serves on the board of Wal-Mart Stores (WMT) .

10. Phebe N. Novakovic
General Dynamics Corp. (GD - Get Report)

Market Cap: $45.2 billion
Became CEO in 2013
Age: 57
2013 Compensation: $19 million

Phebe Novakovic has been chairman and CEO of the aerospace company since Jan. 1, 2013, where she was promoted from the chief operating officer position at General Dynamics. Novakovic has held various vice president and executive roles at the company since 2001. Prior to her role in corporate America, Novakovic worked for the CIA and the U.S. Department of Defense.

 

9. Lynn J. Good
Duke Energy (DUK - Get Report)
Market Cap: $57.8 billion
Became CEO in 2013
Age: 54
2013 Compensation: $6.5 million

Lynn Good has been CEO of Duke Energy since July 2013, after being promoted from the position of chief financial officer. Good is also vice chair of the board of directors. Good came on board at Duke Energy following the electric power company's merger with Cinergy in 2006, where she served in a variety of financial positions, including chief financial officer.


8. Mary T. Barra
General Motors (GM - Get Report)
Market Cap: $60.6 billion
Became CEO in 2014
Age: 53
2013 Compensation: $5.2 million (as executive vice president of global product development purchasing and supply chain)

Mary Barra was appointed CEO of General Motors in January 2014 after serving briefly as the automaker's executive vice president of global product development purchasing and supply chain from August 2013. She was the senior vice president of global product development from February 2011 and in these two positions Barra was responsible for the design, engineering, program management and quality of GM vehicles around the world, according to her company biography. Barra is a longtime GM employee, having started there in 1980. Barra has been on the Forbes magazine and Fortune magazine most powerful women in business lists.


7. Marillyn A. Hewson
Lockheed Martin Corp. (LMT - Get Report)
Market Cap: $61.6 billion
Became CEO in 2013
Age: 61
2013 Compensation: $25.1 million

Marillyn Hewson is a longtime Lockheed Martin employee. Throughout her 31-year tenure at the aerospace and defense company, Hewson has held a variety of executive positions including president, chief operating officer and executive vice president of Lockheed Martin's Electronic Systems business, as well as operational leadership roles.

Hewson serves on the board of directors of DuPont. In September 2013, she was appointed by President Obama to the President's Export Council, the principal national advisory committee on international trade. Hewson has been selected by Fortune magazine as one of the most powerful women in business for the past five years.

6. Irene B. Rosenfeld
Mondelez International (MDLZ - Get Report)
Market Cap: $61.7 billion
Became CEO in 2012
Age: 62
2013 Compensation: $13.9 million

Irene Rosenfeld is Mondelez International's chairman and CEO, positions she took when the snack food company Kraft Foods split itself in two in 2012. She was previously the CEO and chairman of Kraft Foods since 2006.

Rosenfeld is a 30-year veteran of the food industry and has served in executive positions at Frito Lay, a division of PepsiCo, and General Foods (acquired by a predecessor to Altria Group  (MO) . 

The Financial Times, Fortune and Forbes have repeatedly ranked Irene on their lists of the "Top 50 Women in Global Business," "50 Most Powerful Women in Business" and as one of the world's "100 Most Powerful Women."

5. Ellen Kullman
E. l. duPont De Nemours & Co. (DD - Get Report)
Market Cap: $68.1 billion
Became CEO in 2009
Age: 59
2013 Compensation: $14.1 million

Ellen Kullman has been DuPont's chairman and CEO since 2009 and the nineteenth CEO since the chemicals company was founded in 1802. Kullman began her career at DuPont in 1988 as a marketing manager for its medical imaging business. Kullman also sits on the board of United Technologies (UTX) .

She has been named to both Fortune and Forbes' magazine's most powerful women lists.

4. Meg Whitman
Hewlett Packard (HPQ - Get Report)

Market Cap: $70 billion
Became CEO in 2011
Age: 58
2013 Compensation: $17.6 million

Hewlett Packard CEO Meg Whitman came on board in 2011 and became chairman in 2014. She served as president and CEO of eBay (EBAY) from 1998 to 2008. Whitman is a director at Procter & Gamble.

The company announced plans in October to split into two companies -- Hewlett-Packard Enterprise, which will comprise its enterprise technology infrastructure and software and services businesses, and HP Inc., which will encompass personal systems and printing business. Whitman will be president and CEO of Hewlett-Packard Enterprise when the transaction is completed by the end of 2015.

 

3. Indra K. Nooyi
PepsiCo (PEP - Get Report)
Market Cap: $150.2 billion
Became CEO in 2006
Age: 61
2013 Compensation: $14.2 million

Indra Nooyi is Chairman and Chief Executive Officer of PepsiCo, the global food and beverage company that has 22 brands that generate more than $1 billion in annual retail sales.

Nooyi, a Pepsi veteran since 1994, was named president and CEO on October 1, 2006 and assumed the role of chairman in May 2007. She has directed the company's global strategy for more than a decade as well as its restructuring, including the divestiture of its restaurants into Yum! Brands (YUM) , the acquisition of Tropicana and the merger with Quaker Oats that brought Quaker and Gatorade businesses to PepsiCo, among others, according to her corporate biography.

Nooyi began her career in India, where she held product manager positions at Johnson & Johnson and at Mettur Beardsell, a textile firm.

2. Virginia M. Rometty
IBM (IBM - Get Report)
Market Cap: $156.7 billion
Became CEO in 2012
Age: 57
2013 Compensation: $13.9 million

Virginia "Ginni" Rometty was appointed president and CEO of IBM in January 2012 and the tech company's chairman later that year.

A longtime IBM employee, she began her career there in 1981 in Detroit and has held a number of leadership positions there. Prior to becoming CEO, Rometty was the senior vice president and group executive of IBM's sales, marketing and strategy division where she was responsible for business results in the 170 global markets in which IBM operates and pioneered IBM's rapid expansion in the emerging economies of the world, according to her corporate biography.

1. Safra A. Catz
Oracle Corp. (ORCL - Get Report)
Market Cap: $190.4 billion
Became Co-CEO in 2014
Age: 53
2013 Compensation: $37.6 million (as chief financial officer)

Safra Catz, a longtime Oracle employee, became co-heir to Larry Ellison's company when he gave up the daily management reins in September 2014. (Ellison is executive chairman and chief technology officer.) Previously president and chief financial officer, Catz shares her position with Mark Hurd, who also previously shared the role of president of Oracle.

Catz has been with the company since 1999 and rose through the ranks.