Statement:
An average person in Singapore drinks less alcohol than in Tonga

In the Alcohol average daily consumption rating Singapore holds position #149 2016 out of 189 and Tonga is #121 out of 189 2016.
Position of Singapore is better than position of Tonga.
Both countries holds average positions in the "Alcohol average daily consumption" rating. So Both sexes is an average for both Singapore and Tonga, compared to most countries of the World.

Referencies:

  1. Alcohol average daily consumption 2016 by WHO
    The countries in the rating sorted by 'Both sexes' in descending order.
    Singapore 'Both sexes' value is 6.3
    Tonga 'Both sexes' value is 23.1