The doo-wop progression (I-vi-IV-V) and its '50s variants, the chord loop behind countless 1950s ballads.
17 of the 22 Beatle-written songs carrying the '50s variant' harmony device are John Lennon's, more than any other Beatle (Paul McCartney has 8).
Song count per year
% of each member's catalogue with this tag (by writing credit)
as Em → C → D → G
as G → Em → C → D7
as C♯m → A → B7 → E6
as Dm → B♭ → C7 → Fsus4
as Gm → E♭/B♭ → F7 → B♭
as Am → F → G → C
Updated
Book
Harmony & Voice Leading
Aldwell & Schachter
Book
The Beatles: Complete Scores
Hal Leonard
Sheet music
Musicnotes – Beatles Piano/Vocal/Guitar
Musicnotes
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