I have a number of rows of data with ages of individuals.

I'd like to count the number of ages, but not all individually.

For example, I'd like to count the total number of 6 - 12 year olds in my
column of ages, etc.

I've been using =COUNTIF(A:A, 1) and then adding them all together, but I
don't want to have to do this for all the numbers from 0 - 86 (my highest
number).

Thanks so much.