Interesting exercise.
I looked at my all-time favourite albums list (which actually dates back to the 90s and gets updated from time to time) and came up with the following:
Tori Amos, Boys for Pele (1996)
Tori Amos, Under The Pink (1994)
Radiohead, OK Computer (1997)
Tori Amos, Little Earthquakes (1991)
Richard Thompson, Celtschmerz (1998)
Jeff Buckley, Grace (1994)
Elvis Costello, The Juliet Letters (1993)
Jimmy Webb, 10 Easy Pieces (1996)
Paula Cole, This Fire (1996)
Andrew Bird, The Mysterious Production of Eggs (2004)
That's coincidentally exactly ten out of a list of about fifty and the ratio is 9:1 in favour of the nineties. Then I tweaked the list for the current task and got the following:
Tori Amos, Boys for Pele (1996)
Radiohead, OK Computer (1997)
Ben Folds Five, Whatever and Ever Amen (1997)
Jeff Buckley, Grace (1994)
Andrew Bird, The Mysterious Production of Eggs (2004)
Sufjan Stevens, Seven Swans (2004)
Ryan Adams, Gold (2001)
Ani Difranco, Evolve (2003)
Radiohead, In Rainbows (2007)
Nine Horses, Snow Borne Sorrow (2005)
6:4 to the oughts, which is what I went with.