One row is one country's mid-year population in one year, in millions: Year, Country, Population_Millions. 40 rows.
Part of the Verdant Union datasets, invented teaching data about a fictional union of five countries (Arvenia, Brisland, Coralis, Dovrena, Estmark) built to behave like real environmental statistics. Source: LucidPlexus, dataset page https://lucidplexus.com/community/dataset.php?slug=carboncoxial