On page 2 I suggested the cause is 'inequality' inside the nation. Not Rich or poor nations. Nobody liked that idea.
Here is my key source. A 17 minute TED talk.
How economic inequality harms societies
2,686,640 views • 16:54 min. • Subtitles (transcript in English, etc.) in 40 languages
https://www.ted.com/talks/richard_wilki ... n#t-987398At the 2:59 mark he says,
"Now I'm going to show you what that does to our societies. We collected data on problems with social gradients, the kind of problems that are more common at the bottom of the social ladder. Internationally comparable data on life expectancy, on kids' maths and literacy scores, on infant mortality rates, homicide rates, proportion of the population in prison, teenage birthrates, levels of trust, obesity, mental illness -- which in standard diagnostic classification includes drug and alcohol addiction -- and social mobility. We put them all in one index. They're all weighted equally. Where a country is is a sort of average score on these things. And there, you see it [in the graph he shows] in relation to the measure of inequality [inside the nation between income levels] I've just shown you, which I shall use over and over again in the data. The more unequal countries are doing worse on all these kinds of social problems. It's an extraordinarily close correlation [looking at inside the nation]. But if you look at that same index of health and social problems in relation to GNP per capita [See the graph he shows comparing different nations], gross national income, there's nothing there, no correlation anymore."
At 4:11 mark he says,
"We were a little bit worried that people might think we'd been choosing problems to suit our argument and just manufactured this evidence, so we also did a paper in the British Medical Journal on the UNICEF index of child well-being. It has 40 different components put together by other people. It contains whether kids can talk to their parents, whether they have books at home, what immunization rates are like, whether there's bullying at school. Everything goes into it. Here it is [see the graph he shows] in relation to that same measure of inequality [within the same nation]. Kids do worse in the more unequal societies. Highly significant relationship. But once again, if you look at [on the graph he shows] that measure of child well-being, in relation to national income per person [comparing different nations], there's no relationship, no suggestion of a relationship."
Yes, he doesn't talk much about suicides. But, it is a small component of the index he does use. So, suicides are mixed in with alot of other negative social measures like infant mortality and high school dropout rates, etc.
I think the data would be the same if we just looked at suicides.
If the between nations data you-all are looking at shows this correlation then it would be even stronger if we looked at inside those nations. That is, the higher suicide rate as you go down the income ladder is so high that it effects the national per capita rate, pushing it up for all the richer [more developed] nations.