I'm prickling at the idea of 18-35 being a reasonable age range as a generation
the ludicrosity of this becomes blatant if you expand it just slightly to 18-36. the 36 year old is twice as old as the 18 year old.

(now, age them both 18 years, and you've got a 36 year old and a 54 year old—they might have more in common...?)