I didn't intend to revisit the Australian tobacco sales data again. The only remarkable thing about them is that, after years of decline, they didn't fall in the first year of plain packaging. In fact, the latest set of figures (which are continually revised) show that they rose every quarter.
I have shown this several times in graphs but, for the avoidance of doubt, here are the seasonally adjusted chain volume figures in numbers for the year before plain packaging began and the year after. You can check them here if you wish. Look for column AM.
March 2012: $3,856m
June 2012: $3,822m
September 2012: $3,819m
Dec 2012: $3,680m
*Plain packaging introduced*
March 2013: $3,688m
June 2013: $3,721m
September 2013: $3,756m
December 2013: $3,761m
Considering that the black market in tobacco also grew significantly in 2013, plain packaging looks like the dog's dinner of a policy that it is.
However, in the second year of plain packaging, there was a stonking tax rise on cigarettes and the decline resumed (probably aided by the growth of e-cigarettes). This has saved the anti-smokers' blushes in the eyes of anyone too thick to see what's going on. They can now truthfully say that fewer cigarettes are being bought (legally, anyway) than before the policy was introduced.
This is what the graph looks like with the most recent quarters included...
That's not good enough for the retired sociologist Simon Chapman, currently residing at Sydney Nursing Home for the Terminally Deluded, who has hilariously declared victory by tweeting a graph that compares each quarter to the same quarter of the previous year. He gets some of the figures wrong, but that is probably just routine incompetence. His reason for looking at the data this way is that it has the effect of smoothing out the rises in 2013 and exaggerating the scale of the decline in 2014.
In effect, he is using the fact that sales rose in the first year of plain packaging to amplify the decline in the year after the tax rise. This subterfuge depends on his audience not knowing when plain packaging was introduced (naturally, Chapman doesn't bother to flag up the start date of either plain packaging or the tax rise in his graph) but since most of his followers are true believers and/or idiots, he can be confident of getting away with it.