unfortunately stats like this are about as useful as the kind of crap you get on beauty moisturiser ads.
What would be far more useful would be, for example the modal and mean consumption per week of all those that do drink. Possibly also the mean and modal amount drunk at each session too.
This would give a better comparative picture of the culture of consumption in a particular area. Unfortunately that kind of data is more expensive to collate than simply divide some customs and excise figures on duty from sales by the population number to grab a headline.