 It's a striking comparison to the hard work ethic that this country has been built on. Now, if you're wondering who is a millennial, who's Gen Z? Well, millennials are those who were born between nineteen eighty one and ninety six. And Gen Z are those between the ages of nine born between ninety seven and twenty twelve. That would make up a good majority of your workforce now between the ages of twelve and forty three as of this year.