Men 85% -- Women 15%

The ratio of male to female suicide is 85/15. This seems to hold in all age brackets, from the most likely time to do yourself in 15-24, to the it's all over anyway except the pain so why don't I pull the plug elderly opt out.

Why this ratio? Consider that men are jailed at even a higher rate for homicide, typically in the mid 90th percentile. Men are more violent than women. It could be argued that men have more societal pressure to succeed, more financial burdens: these take a toll, especially when failure is involved. Genetically (and all is genetic here, perhaps) men are more likely to have mutations than women. So on the fringe, those suicides of genetic instability will skew towards men, simply because men express more genetic variations at the fringes. (why? women's more complex reproductive systems select against variability). Though this accounts for only a few percentage points off the norm.
Perhaps men in general have fewer deep intimate ties to other people. Certainly pregnancy, carrying a child, etc, is wildly influential in women, and absent in men.

And of course, deep down, men know they are expendable. So they act like it.