The United States is currently populated by six generations: Silents (born 1925–1945), Boomers (1946–1964), Generation X (1965–1979), Millennials (1980–1994), Generation Z (aka iGen or Zoomers, 1995–2012), and an as-yet-unnamed generation born after 2013 (I call them Polars; some marketers have called them Alphas).
