I know whitetails but not elk...

How old is a mature elk?
What is the general rate of growth?

ie.. a spike? is how old? then next year he'll be a what? 3x3?

how old is a 4x4? 5x5?

how old is a 6x6 300-320" elk? a 350"?

let's not talk exceptions to rules here, but in general/decent/good areas.