Kelly:
Miss Independent - 20
Low - 11
Breakaway - 46
Since u Been Gone - 46
Behind these hazel eyes - 34
Because of You - 37
Walk Away - 29
Never Again - 16
My Life Would Suck without You - 24
Already Gone - 31
I Do Not Hook Up - 18
Mr Know it All - 23
Stronger - 37
Dark Side - 15
Catch My Breath - 24
People Like Us - 10
Rihanna We Found Love - 41
Rihanna Umbrella - 33
Rihanna SOS - 28
Rihanna Take A Bow - 27
Rihanna Only Girl - 27
Rihanna Pon De Replay - 27
Rihanna Diamonds - 26
Kelly:
Miss Independent - 20
Low - 11
Breakaway - 46 Since u Been Gone - 46
Behind these hazel eyes - 34
Because of You - 37
Walk Away - 29
Never Again - 16
My Life Would Suck without You - 24
Already Gone - 31
I Do Not Hook Up - 18
Mr Know it All - 23
Stronger - 37
Dark Side - 15
Catch My Breath - 24
People Like Us - 10
DEMI LOVATO Heart Attack (21 Weeks)
DEMI LOVATO Let it Go (20 Weeks SO FAR)
DEMI LOVATO Skyscraper (15 Weeks)
DEMI LOVATO Here We Go Again (9 Weeks)
DEMI LOVATO This Is Me (8 Weeks)
DEMI LOVATO Get Back (6 Weeks [lol])
DEMI LOVATO Heart Attack (21 Weeks)
DEMI LOVATO Skyscraper (15 Weeks)
DEMI LOVATO Here We Go Again (9 Weeks)
DEMI LOVATO This Is Me (8 Weeks)
DEMI LOVATO Get Back (6 Weeks [lol])
What about her "Let It Go" ? it was the only official single from the OST and stayed 20 weeks so far.