Original sentence: The term is popularly associated with the people born between, roughly,  1961 and 1981 , although this is disputed.There are some older Generation Xers who frown upon the classification of those born in 1980 or 1981 as being part of Generation X; these individuals often prefer to classify Generation X as those born between 1964 and the mid to late 70's
Edited sentence: The term is popularly associated with the people born between 1961 and 1977, although this is disputed