On March 1, 2018, Michael Dimock, President of Pew Research Center, reported that, in terms of Pew’s research endeavors, “Anyone born between 1981 and 1996 (ages 22-37 in 2018) will be considered a Millennial [Gen Y], and anyone born from 1997 onward will be part of a new generation.” Pew is referring to those born after 1996 as “post-Millennials.” (Other sources have begun referring to this new generation as Generation Z, Boomlets, or iGeneration.)
To learn more about Pew’s rationale for the Gen Y date range, see the article linked below.
Dimock, M. (2018). Defining generations: Where Millennials end and post-Millennials begin. Facttank: News in the Numbers. Pew Research Center. Retrieved from http://www.pewresearch.org/fact-tank/2018/03/01/defining-generations-where-millennials-end-and-post-millennials-begin/