Duodecades are superior to decades, and we can take overlapping pairs of duodecades as "generations" to solve the dividing line problem.

Duodecades:

  * 1968-1980
  * 1980-1992
  * 1992-2004
  * 2004-2016
  * 2016-2028

Overlapping generations:

  * GenX: 1968-1992
  * Millennial: 1980-2004
  * GenZ: 1992-2016