Should Mariah Carey be worried about Rihanna stealing her Crown?

Mariah Carey has had the most number one singles on the American Billboard charts of any solo act, but with Rihanna scoring her tenth Number one with the Britney Spears featured S and M , should Carey be worried about the young upstart stealing her crown in the near future? Perhaps more worrying for Carey is that it took her till the age of 25 to score her 9th Number 1 with Fantasy where as the Barbadian singer had already scored the equivalent at the tender age of 22.

Do you think Mariah Carey needs to be worried about Rihanna?
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Mariah Carey's Number 1s:

1. "Vision Of Love" 1990
2. "Love Takes Time" 1991
3. "Someday " 1991
4. "I Don't Wanna Cry" 1991
5. "Emotions" 1992
6. "I'll Be There" 1993
7. "Hero" 1993
8. "Dream Lover" 1995
9. "Fantasy" 1995
10. "One Sweet Day" 1996
11. "Always Be My Baby" 1996
12. "Honey" 1997
13. "My All" 1998
14. "Heart breaker" 1999
15. "Thank God I Found You"2005
16. "We Belong Together" 2005
17. "Don't Forget About Us" 2008
18. "Touch My Body" 2008

Rihanna's Number 1s:

1. "SoS" 2006
2. "Umbrella" 2007
3. "Take A Bow" 2008
4. "Disturbia" 2008
5. "Live Your Life" 2008
6. "Rude Boy" 2010
7. "Love The Way You Lie"2010
8. "What's My Name" 2010
9. "Only Girl (in the world)" 2010
10. "S and M" 2011