using System;

using System.ComponentModel.DataAnnotations;

using System.Reflection;

public class Program

{

    public enum SchoolEnrollmentLevel

    {

        [Display(Name = "499 and under")]

        Under_500 = 1,

        [Display(Name = "500-999")]

        _500_999 = 2,

        [Display(Name = "1,000-1,499")]

        _1000_1499 = 3,

        [Display(Name = "1,500 and over")]

        Over_1500 = 4

    }

    public static string GetEnumDisplayName(Enum enumValue)

    {

        var displayAttribute = enumValue.GetType().GetField(enumValue.ToString()).GetCustomAttribute<DisplayAttribute>();

        return displayAttribute?.Name ?? enumValue.ToString();

    }

    public static void Main()

    {

        PrintFees(SchoolEnrollmentLevel.Under_500);

        Console.WriteLine();

        PrintFees(SchoolEnrollmentLevel._500_999);

        Console.WriteLine();

        PrintFees(SchoolEnrollmentLevel._1000_1499);

        Console.WriteLine();

        PrintFees(SchoolEnrollmentLevel.Over_1500);

​

    }

    public static void PrintFees(SchoolEnrollmentLevel enrollmentLevel)

    {

        var index = 1;

        Console.WriteLine(GetEnumDisplayName(enrollmentLevel));

        while(index < 13){

            Console.WriteLine($"Month {index}: {CalculateNewMembershipFee(index, enrollmentLevel).ToString("$#000.00")}");

            index++;

        }

    }

​

    public static decimal CalculateNewMembershipFee(int month, SchoolEnrollmentLevel level)

    {

        var enrollmentFee = 0M;

        if (month < 1 || month > 12)

        {

            throw new IndexOutOfRangeException();

        }

​

        switch (level)

        {

            case SchoolEnrollmentLevel.Under_500:

                {

                    enrollmentFee = 750M;

                    break;

                }

            case SchoolEnrollmentLevel._500_999:

                {

                    enrollmentFee = 1000M;

                    break;

                }

            case SchoolEnrollmentLevel._1000_1499:

                {

                    enrollmentFee = 1500M;

                    break;

                }

            case SchoolEnrollmentLevel.Over_1500:

                {

                    enrollmentFee = 2000M;

                    break;

                }

            default:

                { 

                    throw new IndexOutOfRangeException(); 

                }

        }

​

        var result = month * (1M / 12M) * enrollmentFee;

​

        return result;

    }

}

​