from https://meta.wikimedia.org/wiki/Research:Standard_metrics
2.1 Newly registered user
2.2 New editor
2.4 Surviving new editor
3.2.4 Daily unique page creators
3.2.5 Daily unique media creators
4.5 Daily pages created
4.6 Daily media created
3.1.1 Rolling active editor
3.1.2 Rolling new active editor
3.1.3 Rolling surviving new active editor
3.1.4 Rolling recurring old active editor
3.1.5 Rolling re-activated editor