International trade in food is an essential component of the global food system, with consequences ranging from environmental sustainability to public health. Evidence-based food policy requires analysis and interpretation of trade flows among countries.

The PACHS22 is a multipurpose goods nomenclature that forms the basis for Customs Tariffs and International Merchandise Trade Statistics and has been derived from the World Customs Organisation’s (WCO's) HS22.

Medical certification of cause of death (MCCD) is a key source of mortality statistics. The death certificate is a permanent record of the fact and characteristics of death. It provides important personal information about the decedent, the circumstances and the cause of death.

Tonga's fourth Household Income and Expenditure Survey (HIES) undertaken by Tonga Statistics Department (TSD). The previous HIES took place in 2001, 2009 and 2015.