1) In order to preserve statistical secrecy, we show only those surnames whose frequency is greater than 5 in either of the two surnames, for the national total. For the selected nationalities, it is required too a frequency of at least 5 in either of the two surnames. For this reason, the total national frequency for some surnames may not be equal to the sum of the nationalities shown.
2) Data taken from the Continuous Register Statistics with date 01/01/2012.