For the years 1980 to 1984 the data sources are
EIA
and
IEA (imports/exports).
For the years 1990 to 2006 the data source is
IEA.
For the year 2007 the data source is
Ember.
For the years 2008 to 2015 the data source is
IEA.
For the year 2016 the data source is
Ember.
For the years 2017 to 2019 the data source is
IEA.
For the years 2020 to 2021 the data source is
Ember.