Actually tD, it's not. In fact is really the worst way of measuring smoking.
Following the most recent increases in cigarette taxes in NY and NJ Delaware sales of cigarettes skyrocketted. Smoking in Delaware didn't increase, just the sale of the product.
The antis claim that a drop in sales is proof positive that smokers are quitting in droves yet turn around and run to the nearest jurisdiction with a lower tax to try to convince them to increase the tax.
Increased taxes absolutely and always will lead to less purchase...........less purchase in the higher tax venue does not equate to less use of the overly taxed product.
... but I can't give it proper consideration without a Cohiba to accompany my musings.