A Japanese Depression

A recent study has come out showing that almost 10% of all Japanese teenagers are depressed or have manic depression. The study shows that normal factors such as time spend outside and diet do not seem to be playing a role. I would like to see if ethnically Japanese people living in other locations (such as in the United States, Korea, ect) have the same rate of depression. I wonder if the famously stoic culture contributes to the rate of depression among youths. Japan is the most secular society in the world (among societies with religious freedom) so I wonder how the depression rate for Japan would compare to those in South Korea which is culturally and environmentally quite similar but much more religious.