Why British youth are turning off alcohol
theguardian.com
theguardian.com
I also see people make a conscious active decision to alter their states of mind. Say for a particular party, or for a particular sunny Sunday afternoon. And alcohol is normally only a small part of the picture in this regard.
I suspect any study that only looks at alcohol consumption is going to see a very limited view of any overall social trend.
I would be very interested to see data about drug consumption, broken down by substance, alcohol included.
Edit: this could also be seen as a regression to the mean. UK drinking culture has been a bit extreme.