Authorship and Collaboration: This graph (based on authorial attributions quantified by William J. Dowdling in the book Beatlesongs) traces songwriting contributions within the band.
NOTES: Color patterns offer clues about the band’s gradual fracturing as each member becomes more independent. Red stalks (signifying jointly written songs) decrease in the second half of the timeline; the split-color bars give way to solid bars of a single color. George Harrison also began to compose more music as he matured as a songwriter, signified by the increase in green bars (Lennon and McCartney’s lack of support through Harrison’s development is widely cited as a factor contributing to the band’s eventual breakup).
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