Yes I have. I could post sources all day about this, everything I said is well backed up by the available research.

Data from the ABS also indicates the rate of suicide by firearm fell by 67 per cent from 2.1 deaths per 100,000 of the population in 1996 to 0.7 deaths in 2014.

and

Other research argues the reforms accelerated the rates of decline, with one study suggesting firearm suicides dropped by 74 per cent from the 1990-95 average following the buyback scheme.

source Snopes Peer reviewed study from American Law and Economics Review 2012 Guardian

As usual there's always debates with these kind of things because rate of suicide is something that encompasses a lot of variables, but the fact remains that the suicide rates did drop considerably. As they did with all of the examples I gave above. There is some very good research on all of them, particularly the examples of the bridge barriers and coal gas ovens. I suspected if anyone tried to query this they'd focus on the gun stats. People lurve dem der guns.

What data are you talking about?