An invoice total without VAT MUST equal the sum of line amounts plus the sum of charges on document level minus the sum of allowances on document level
//cac:LegalMonetaryTotal((cbc:ChargeTotalAmount) and (cbc:AllowanceTotalAmount) and ((xs:decimal(cbc:TaxExclusiveAmount)) = round((xs:decimal(cbc:LineExtensionAmount) + xs:decimal(cbc:ChargeTotalAmount) - xs:decimal(cbc:AllowanceTotalAmount)) * 10 * 10) div 100 )) or (not(cbc:ChargeTotalAmount) and (cbc:AllowanceTotalAmount) and ((xs:decimal(cbc:TaxExclusiveAmount)) = round((xs:decimal(cbc:LineExtensionAmount) - xs:decimal(cbc:AllowanceTotalAmount)) * 10 * 10 ) div 100)) or ((cbc:ChargeTotalAmount) and not(cbc:AllowanceTotalAmount) and ((xs:decimal(cbc:TaxExclusiveAmount)) = round((xs:decimal(cbc:LineExtensionAmount) + xs:decimal(cbc:ChargeTotalAmount)) * 10 * 10 ) div 100)) or (not(cbc:ChargeTotalAmount) and not(cbc:AllowanceTotalAmount) and (xs:decimal(cbc:TaxExclusiveAmount) = xs:decimal(cbc:LineExtensionAmount)))