Well over 10. I'm in my 60's and the very first time I was depressed was in grade school. We had a wonderful principal and she got me alone one day and so very concerned asked me what was wrong as I no longer smiled and laughed. Boy I was so tempted to just cry in her arms but I just shrugged and shuffled off. The bipoar didn't trip until I was in my 20's and as Christina mentioned it's so shiny and usually I have delusional thinking so I don't seek help and I usually skip doctors and therapists appointment s so it really delayed the diagnosis.