It's all said and done?

Take into account how long their careers will last from this point on because they will only be able to earn Grammys if they're popular. Nominations are rarely earned if you're completely irrelevant.

Currently Grammy wins:

Beyoncé: 20
Alicia: 15
Adele: 10
Rihanna: 8
Madonna: 7
Taylor: 7
Gaga: 6
Mariah: 5
Celine: 5
Christina: 5
Kelly: 3
Britney: 1
Katy: 0
Demi: 0
Selena: 0

Beyonce: 27
Adele: 24
Taylor: 16
Rihanna: 13
Gaga: 8
Madonna: 7
Katy: 1

How many Grammys will win these artists until they stop being popular and cool?

For example Madonna, Mariah and Celine are done with the Grammys so they probably won't be winning another one.

Beyoncé: 20 -> 32
Alicia: 15 -> 18
Adele: 10 -> 25
Rihanna: 8 -> 11
Madonna: 7 -> 8
Taylor: 7 -> 13
Gaga: 6 -> 10
Mariah: 5 -> 4 lol jk but the Grammys really hate her though. That 2005 snub -_-
Celine: 5 -> 5
Christina: 5 -> 7
Kelly: 3 -> 3
Britney: 1 -> mmmm
Katy: 0 -> 1. She will have her Toxic in 5-6 years I guess.
Demi: 0 -> mm
Selena: 0 -> mmm