The Music of What Happens

• The Allman Brothers Band, Live At Fillmore East, 1971
• The Beatles, Abbey Road, 1969
• The Cure, Disintegration, 1989
• Derek and the Dominos, The Layla Sessions, 1991
• The Doors, Box Set, 1997
• Keith Emerson and the Nice, Keith Emerson and the Nice, 1973
• Gov't Mule, Live, With a Little Help from our Friends, 2001
• David Gray, White Ladder, 2000
• Elton John, Madman Across the Water, 1971
• Little Feat, Waiting for Columbus, 1977
• Los Lobos, Just Another Band from East LA, 1993
• Van Morrison, St Dominics Preview, 1972
• Van Morrison, Veedon Fleece, 1974
• Van Morrison, The Philosopher's Stone, 1998
• Quicksilver, Just for Love, 1970
• Renaissance, Tales of 1001 Nights I and II, 1997
• The Rolling Stones, Sticky Fingers, 1971
• Todd Rundgren, Something/Anything, 1971
• Sade, Promise, 1985
• Santana, Caravanserai, 1971
• Seal, Seal, 1991
• Al Stewart, Rhymes in Rooms, 1997
• Tears for Fears, The Seeds of Love
• Traffic, The Low Spark of High Heeled Boys, 1972
• The Who, Who's Next, 1972
• Steve Winwood, Steve Winwood, 1977
• Yes, The Yes Album, 1970
• Yes, Tales from Topographic Oceans, 1974
• Neil Young, Everybody Knows This is Nowhere, 1971

Okay. Most of what I included was recorded in 1969-1974. Much of the 90s material are collections of material, much of which was recorded in the 70's. Why?