public static IList <DateTime> GetNonWorkingDays(int year)
    {
        IList <DateTime> days = new List <DateTime>();

        days.Add(new DateTime(year, 01, 01));
        days.Add(new DateTime(year, 01, 06));
        days.Add(new DateTime(year, 04, 25));
        days.Add(new DateTime(year, 05, 01));
        days.Add(new DateTime(year, 06, 02));
        days.Add(new DateTime(year, 06, 24));
        days.Add(new DateTime(year, 08, 15));
        days.Add(new DateTime(year, 10, 01));
        days.Add(new DateTime(year, 12, 08));
        days.Add(new DateTime(year, 12, 25));
        days.Add(new DateTime(year, 12, 26));
        days.Add(NonWorkingDays.EasterDay(year));
        days.Add(NonWorkingDays.EasterDay(year).AddDays(1));


        DateTime dummy = new DateTime(year, 1, 1);

        while (dummy.Year == year)
        {
            if (!days.Contains(dummy) && dummy.DayOfWeek == DayOfWeek.Saturday || dummy.DayOfWeek == DayOfWeek.Sunday)
            {
                days.Add(dummy);
            }

            dummy = dummy.AddDays(1);
        }

        return(days);//a
    }