Changes made by Commission Implementing Decision of 10 December 2013 authorising Portugal to use certain approximate estimates and to use statistics for years earlier than the last year but one for the calculation of the VAT own resources base (notified under document C(2013) 8689) (Only the Portuguese text is authentic) (2013/749/EU, Euratom)
EU Decision 2013/749
No changes made by Commission Implementing Decision of 10 December 2013 authorising Portugal to use certain approximate estimates and to use statistics for years earlier than the last year but one for the calculation of the VAT own resources base (notified under document C(2013) 8689) (Only the Portuguese text is authentic) (2013/749/EU, Euratom) are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.