2013 - present
http://data.okfn.org/roadmap/core-datasets/
Core Datasets are Important, commonly-used datasets in high quality, easy-to-use & open form.
Core Datasets are including a set of key reference and indicator datasets such as country codes, currencies, GDP and population.
All datasets are provided in a standardized form and can be accessed in bulk as CSV together with a simple JSON schema. Also, all data is in data packages and is versioned using git so all changes are visible and data can be collaboratively maintained.