Country A country representation. This can be used to link to other knowledge graphs. Entry An entry is used for a measurement, which is taken at least per year and per country. It has only it's value and no additional properties. The difference to an event is, that it is actively measured instead of passively recognized. Event An event occours depending to a specific time and is usually located within a specific country. Source The source class is used to describe meta data of each subclass of Entry and Event. entry Link an entry to a country. event Link an event to a country. importdate the exact date when a dataset has been imported to the knowledge graph. licence If possible or required, provide a licence when publishing data. oftype Name the subclass of an entry or an event to link the source's metadata to it. unit The unit of data from a datasource, value The value of a measurement. timeline:atYear The year the measurement (entry) or the event has been taken or belongs to.