Generations: The Real Differences Between Gen Z, Millennials, Gen X, Boomers, and Silents—and What They Mean for America's Future

by Jean M. Twenge

Most of the people who died on 9/11 were in the prime of their lives, in their 20s, 30s, and 40s; nearly 90% were Gen X’ers and Boomers, including the firefighters and police officers who died in the line of duty.