[SCH-EUSR-44] MUST have one CC Key element with the scheme ID 'EndUserCountry'
SCH-EUSR-44
/eusr:EndUserStatisticsReport/eusr:Subset[normalize-space(@type) = 'PerDT-EUC']
count(eusr:Key[normalize-space(@metaSchemeID) = 'CC'][normalize-space(@schemeID) = 'EndUserCountry']) = 1