Also, prior to enacting gun control, Australia's non-firearm suicide rate doubled (1980-1996) while firearm suicide was cut in half.
Not sure there is any correlation.
And for the US - http://www.slate.com/articles/news_and_politics/crime/2013/1...
[1]https://en.wikipedia.org/wiki/Gun_laws_in_Australia#Measurin...
"The results of these tests suggest that the NFA did not have any large effects on reducing firearm homicide or suicide rates."[61]"
"The implemented restrictions may not be responsible for the observed reductions in firearms suicide. Data suggest that a change in social and cultural attitudes could have contributed to the shift in method preference.[60]"
I wouldn't assume that it's settled.
The table I'm looking at says firearm suicides dropped by 50% prior to the gun buyback.
I'd argue the decrease in overall suicides is a general trend happened to coincide with the gun buyback.