private const string civicNumberValidationPatternSwedish =
            @"^(?<date>(?<year>(19|20)?\d{2})(?<month>\d{2})(?<day>\d{2}))[-\+]?(?<additional>\d{3})(?<checkdigit>\d{1})$"; //Swedish

        private const string civicNumberValidationPatternSwedishForFormatting =
            @"^(?<date>(?<year>\d{4}|\d{2})(?<month>\d{2})(?<day>\d{2}))[-\+]?(?:(?<additional>[A-Z\d]{4,5})){0,1}$"; //Swedish pattern for formatting between countries

        // ddmm(yy)yy-ABCD
        // The year may or may not include the century.
        // The four last digits is a sequence number.
        // The first sequence digit, A, encodes the century of birth.
        // The last digit of the sequence number, D, is odd for males and even for females.
        // The last digit is also a check digit for the entire CPR-number.
        private const string civicNumberValidationPatternDanish =
            @"^(?<date>(?<day>\d{2})(?<month>\d{2})(?<year>(19|20)?\d{2}))[-\+]?(?:(?<additional>\d{3})(?<checkdigit>\d{1})){0,1}$"; //Danish

        //ddmmyy-XXXXX
        private const string civicNumberValidationPatternNorwegian =
        @"^(?<date>(?<day>\d{2})(?<month>\d{2})(?<year>(19|20)?\d{2}))[-\+]?(?<additional>\d{5}){0,1}$"; //Norwegian

        //ddmmyy-XXXX
        private const string civicNumberValidationPatternFinnish =
            @"^(?<date>(?<day>\d{2})(?<month>\d{2})(?<year>(19|20)?\d{2}))[-\+A]?(?:(?<additional>\d{3})(?<checkdigit>[a-zA-Z\d]{1})){0,1}$"; //Finnish