Key variables, for which every effort should be made to avoid missing values and for which imputation is recommended are:
Commission Regulation (EC) No 198/2006Dangos y teitl llawn
Commission Regulation (EC) No 198/2006 of 3 February 2006 implementing Regulation (EC) No 1552/2005 of the European Parliament and the Council on statistics relating to vocational training in enterprises (Text with EEA relevance)