Rihanna
"Pon de Replay" (06/25/2005)
31-19-11-9-8-6-6-6-5-5-4-4-2-2-2-3-6-9-12-14-18-20-22
"If It's Lovin' That You Want" (11/05/2005)
39-34-30-24-22-20-15-14-12-10-10-9-9-10-16-19-27-28-31-31
"SOS" (02/18/2006)
27-23-14-11-10-7-6-4-4-3-2-2-1-2-3-4-5-5-5-8-10-16-18-20
"Unfaithful" (05/13/2006)
34-28-22-17-14-11-9-6-5-3-2-2-2-3-6-10-13-15-18-19
"We Ride" (09/23/2006)
39-35-34-35-37
"Break It Off (feat. Sean Paul)" (11/18/2006)
40-35-32-28-24-21-16-14-14-14-12-10-7-7-6-6-7-10-13-13-15-19
"Umbrella (feat. Jay-Z)" (04/21/2007)
34-25-22-21-16-13-12-8-7-6-2-2-3-3-4-3-5-6-7-10-14-19-20-19
"Shut Up and Drive" (07/07/2007)
35-28-25-23-19-15-13-13-11-12-13-18-22-25-32
"Hate That I Love You (feat. Ne-Yo)" (09/22/2007)
26-23-19-16-13-11-9-7-7-5-3-3-3-4-5-6-5-7-7-8-13-15-18-20
"Don't Stop the Music" (12/29/2007)
33-31-27-23-17-15-9-6-5-5-3-3-3-4-4-6-8-11-14-15-20
"Take a Bow" (04/12/2008)
31-28-24-16-13-10-9-6-5-4-2-2-1-tbc
"If I Never See Your Face Again (Remix) (feat. Rihanna)" (06/07/2008) [Maroon 5 Song]
36-35-34-30-31-tbc
"Disturbia" (07/05/2008)
30-tbc
Britney Spears
"...Baby One More Time" (10/04/1998)
37-28-23-21-16-12-11-9-9-9-6-6-7-7-8-8-6-2-1-1-1-1-1-2-2-2-3-4-6-9-12-12-13-15-18-19
"Sometimes" (05/15/1999)
24-20-12-11-9-8-6-7-6-6-6-6-6-7-12-16-23-34-36
"(You Drive Me) Crazy" (09/11/1999)
29-20-18-16-13-10-7-6-5-4-4-5-8-9-12-17-21-27-26-28-27-32-35-39-off-off-39-40
"From the Bottom of My Broken Heart" (01/22/2000)
33-23-22-17-17-21-25-34
"Oops!... I Did It Again" (04/22/2000)
40-19-11-7-4-3-3-1-1-1-2-6-9-9-13-18-28-34-35-34-37-39
"Lucky" (08/05/2000)
33-20-17-13-13-9-9-9-15-20-29-37
"Stronger" (11/18/2000)
35-28-24-19-19-18-17-18-19-19-24-33-36
"I'm a Slave 4 U" (10/13/2001)
40-30-26-22-21-21-18-15-19-19-22-26-36
"I'm Not a Girl, Not Yet a Woman" (01/26/2002)
34-27-23-22-21-22-30
"Overprotected" (05/04/2002)
40-off-38-37
"Boys" (08/17/2002)
40-38-39
"Me Against the Music (feat. Madonna)" (10/25/2003)
24-13-11-13-11-11-12-22-30-40
"Toxic" (01/24/2004)
39-21-14-9-5-4-3-2-1-1-1-1-3-3-3-5-9-12-13-17-21-20-27-27-29-32
"Everytime" (05/15/2004)
36-27-19-14-8-8-8-5-4-4-4-5-10-14-19-25-31-36
"Outrageous" (08/07/2004)
37-31-26-23-24
"My Prerogative" (10/09/2004)
28-24-22-22-30
"Gimme More" (09/22/2007)
25-20-18-18-17-17-22-31-35-35-37-38-39
"Piece of Me" (12/08/2007)
36-31-32-28-29-28-28-29-30-28-33-36-34-39-39-38-39-40-39-38
"Break the Ice" (03/22/2008)
39-37-34-29-27-29-25-24-24-22-21-25-26-27-32
Britney Spears
"...Baby One More Time" (10/04/1998)
37-28-23-21-16-12-11-9-9-9-6-6-7-7-8-8-6-2-1-1-1-1-1-2-2-2-3-4-6-9-12-12-13-15-18-19
"Sometimes" (05/15/1999)
24-20-12-11-9-8-6-7-6-6-6-6-6-7-12-16-23-34-36
"(You Drive Me) Crazy" (09/11/1999)
29-20-18-16-13-10-7-6-5-4-4-5-8-9-12-17-21-27-26-28-27-32-35-39-off-off-39-40
"From the Bottom of My Broken Heart" (01/22/2000)
33-23-22-17-17-21-25-34
"Oops!... I Did It Again" (04/22/2000)
40-19-11-7-4-3-3-1-1-1-2-6-9-9-13-18-28-34-35-34-37-39
"Lucky" (08/05/2000)
33-20-17-13-13-9-9-9-15-20-29-37
I'm going to stop here for now and pick up with "Stronger" 2morrow!
'Sometimes' peaked at #4, 'From The Bottom...' peaked at #16 and 'Lucky' peaked at #8.