<Table> <Tr> <Th> </Th> <Th> CEO </Th> <Th> Company </Th> <Th> 2017 Fortune 500 ranking </Th> </Tr> <Tr> <Td> </Td> <Td> Mary Barra </Td> <Td> General Motors </Td> <Td> 8 </Td> </Tr> <Tr> <Td> </Td> <Td> Ginni Rometty </Td> <Td> IBM </Td> <Td> 32 </Td> </Tr> <Tr> <Td> </Td> <Td> Indra Nooyi </Td> <Td> PepsiCo </Td> <Td> 44 </Td> </Tr> <Tr> <Td> </Td> <Td> Marillyn Hewson </Td> <Td> Lockheed Martin </Td> <Td> 56 </Td> </Tr> <Tr> <Td> </Td> <Td> Meg Whitman </Td> <Td> Hewlett Packard Enterprise </Td> <Td> 59 </Td> </Tr> <Tr> <Td> 6 </Td> <Td> Safra A. Catz </Td> <Td> Oracle Corporation </Td> <Td> 81 </Td> </Tr> <Tr> <Td> 7 </Td> <Td> Phebe Novakovic </Td> <Td> General Dynamics </Td> <Td> 90 </Td> </Tr> <Tr> <Td> 8 </Td> <Td> Irene Rosenfeld </Td> <Td> Mondelēz International </Td> <Td> 109 </Td> </Tr> <Tr> <Td> 9 </Td> <Td> Tricia Griffith </Td> <Td> Progressive Corporation </Td> <Td> 120 </Td> </Tr> <Tr> <Td> 10 </Td> <Td> Lynn Good </Td> <Td> Duke Energy </Td> <Td> 121 </Td> </Tr> <Tr> <Td> 11 </Td> <Td> Shira Goodman </Td> <Td> Staples Inc . </Td> <Td> 140 </Td> </Tr> <Tr> <Td> 12 </Td> <Td> Geisha Williams </Td> <Td> Pacific Gas and Electric Company </Td> <Td> 157 </Td> </Tr> <Tr> <Td> 13 </Td> <Td> Margaret M. Keane </Td> <Td> Synchrony Financial </Td> <Td> 185 </Td> </Tr> <Tr> <Td> 14 </Td> <Td> Deanna M. Mulligan </Td> <Td> The Guardian Life Insurance Company of America </Td> <Td> 218 </Td> </Tr> <Tr> <Td> 15 </Td> <Td> Barbara Rentler </Td> <Td> Ross Stores </Td> <Td> 219 </Td> </Tr> <Tr> <Td> 16 </Td> <Td> Debra Crew </Td> <Td> Reynolds American </Td> <Td> 223 </Td> </Tr> <Tr> <Td> 17 </Td> <Td> Anna Manning </Td> <Td> Reinsurance Group of America </Td> <Td> 246 </Td> </Tr> <Tr> <Td> 18 </Td> <Td> Vicki Hollub </Td> <Td> Occidental Petroleum </Td> <Td> 278 </Td> </Tr> <Tr> <Td> 19 </Td> <Td> Debra L. Reed </Td> <Td> Sempra Energy </Td> <Td> 280 </Td> </Tr> <Tr> <Td> 20 </Td> <Td> Kathryn V. Marinello </Td> <Td> Hertz Global Holdings </Td> <Td> 296 </Td> </Tr> <Tr> <Td> 21 </Td> <Td> Kimberly S. Bowers </Td> <Td> CST Brands </Td> <Td> 306 </Td> </Tr> <Tr> <Td> 22 </Td> <Td> Mary Laschinger </Td> <Td> Veritiv Corporation </Td> <Td> 331 </Td> </Tr> <Tr> <Td> 23 </Td> <Td> Denise Morrison </Td> <Td> Campbell Soup </Td> <Td> 339 </Td> </Tr> <Tr> <Td> 24 </Td> <Td> Michele Buck </Td> <Td> The Hershey Company </Td> <Td> 369 </Td> </Tr> <Tr> <Td> 25 </Td> <Td> Patti Poppe </Td> <Td> CMS Energy </Td> <Td> 419 </Td> </Tr> <Tr> <Td> 26 </Td> <Td> Kathleen Mazzarella </Td> <Td> Graybar </Td> <Td> 420 </Td> </Tr> <Tr> <Td> 27 </Td> <Td> Sheri McCoy </Td> <Td> Avon Products </Td> <Td> 444 </Td> </Tr> <Tr> <Td> 28 </Td> <Td> Ilene S. Gordon </Td> <Td> Ingredion </Td> <Td> 456 </Td> </Tr> <Tr> <Td> 29 </Td> <Td> Margo Georgiadis </Td> <Td> Mattel </Td> <Td> 474 </Td> </Tr> <Tr> <Td> 30 </Td> <Td> Beth E. Mooney </Td> <Td> KeyBank </Td> <Td> 479 </Td> </Tr> <Tr> <Td> 31 </Td> <Td> Jacqueline Hinman </Td> <Td> CH2M Hill </Td> <Td> 494 </Td> </Tr> <Tr> <Td> 32 </Td> <Td> Marissa Mayer </Td> <Td> Yahoo ! </Td> <Td> 498 </Td> </Tr> </Table>
how many ceos of fortune 500 companies are female
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