Selena Gomez: 2
Come & Get It (#6)
The Heart Wants What It Wants (#6)
She also has Who Says that peaked at #21 and Love You Like A Love Song at #22 
Britney Spears: 5
3 (#1 in 2009, #10 in 2010)
Hold It Against Me (#1)
Till The World Ends (#3)
I Wanna Go (#7)
Work Bitch! (#12)
Miley Cyrus: 4
When I Look At You (#16)
Can't Be Tamed (#8)
We Can't Stop (#2)
Wrecking Ball (#1)
Cher Lloyd: 1
Want U Back (#12)
UK: 1 Swagger Jagger (#1)
Taylor Swift: 19
Mine (#3)
Back To December (#6)
Mean (#11)
Sparks Fly (#17)
Speak Now (#8)
Ours (#13)
Eyes Open (#19)
If This Was A Movie (#10)
We Are Never Ever Getting Back Together (#1)
Ronan (#16)
Begin Again (#7)
I Knew You Were Trouble (#2)
22 (#20)
Red (#6)
State Of Grace (#13)
Shake It Off (#1)
Blank Space (#1)
Style (#6)
Out Of The Woods (#18)
Ellie Goulding: 3
Lights (#2)
Burn (#13)
Love Me Like You Do (#3)
UK: 10 Starry Eyed (#4), The Writer (#19), Your Song (#2), Anything Could Happen (#5), Explosions (#13), Burn (#1), How Long Will I Love You (#3), Goodness Gracious (#16), Beating Heart (#9), Love Me Like You Do (#1)
Fifth Harmony: 0
Haley Reinhart: 0
Ariana Grande: 1
One Last Time (#13)
Marina and the Diamonds: 0
UK: 2 Hollywood (#12), Primadonna (#11)
Foxes: 0
UK: 3 Youth (#12), Let Go For Tonight (#7), Holding Onto Heaven (#14)
