Ok, I've seen you talk about your exact hair length and I'm wondering, how do you go about doing the measuring?
I mean I took a tape and measured from where my hairline starts in the forehead down the whole length. My hair is wavy and it was measured dry.
So is this my hair length? Or should it be a smaller number, i.e. the length from the top of the head downwards? Or should it be done wet? ???

I think the generally accepted method for measuring long hair is to start at the front hairline, over the top of the head, down to the end of the longest hair.  If you have curly/wavy hair, gently pull the hair to straighten it out.  (We don't want to yank out any of that lovely hair!!)  

Wet or dry, I'm not sure it matters a lot, just be consistent.

Yup, what Bikerbraid said. I do it wet because my hair is very wavy, and I like to get an accurate measure of the growth. Wavy hair that changes its wave doesn't give an accurate dry measurement every month.  ;)

Ok, so with my wavy non-pulled-straight dry hair I got the 72cm or 28 1/4 in.
It's a long way to sit-on-them length.  :-/

Ta for the replies  :)