Simplify the following text for a Grade 9 native English-speaking person.
Original: Generation Y , also known as the Millennial Generation ( or Millennials ) , Generation Next , Net Generation , Echo Boomers , describes the demographic cohort following Generation X. As there are no precise dates for when the Millennial generation starts and ends , commentators have used birth dates ranging somewhere from the mid-1970s to the early 2000s . Members of this generation are called Echo Boomers , due to the significant increase in birth rates through the 1980s and into the 1990s , and because many of them are children of baby boomers .
Simplified: People in this generation period are known as Millennials or Echo Boomers .