Exactly. In Ireland the plate is made of [registration year]-[county]-[count of cars registered that year]. 16-D-17891 : the 17891st car registered in Dublin,

Exactly. In Ireland the plate is made of [registration year]-[county]-[count of cars registered that year]. 16-D-17891 : the 17891st car registered in Dublin, in the year 2016. They have recently introduced a third number in the year position to indicate 6 month sections (ie. 161 or 162).