总和平均流阅读器

Question

我需要知道为什么会收到错误消息“使用未分配的局部变量“ totalFee”。我真的很努力地理解这一点，我得到了基本的信息，我正在努力解决所有这些新错误。

       {int[] hoursArray = new int[50];
        const decimal HOURLY_RATE = 2.5M;
        const decimal MAX_FEE = 20.00M;
        decimal parkFee;
        int counter = 0;
        string line;
        decimal totalFee, avFee;

        StreamReader fileSR = new StreamReader("hours.txt");
        //data for hours read from "hours.txt" file
        line = fileSR.ReadLine();
        while (line != null)
        {
            hoursArray[counter] = int.Parse(line);
            counter = counter + 1;
            line = fileSR.ReadLine();
        }

        for (int i = 0; i < hoursArray.Length; i++)
        {
            parkFee = hoursArray[i] * HOURLY_RATE;
            if (parkFee > MAX_FEE)
            {
                parkFee = MAX_FEE;         
            }
            fileSR.Close();
            Console.ReadLine();
            totalFee=totalFee + parkFee;
        }
        avFee = totalFee/hoursArray.Length;
        Console.WriteLine("The average parking fee is " + avFee.ToString("N2"));

Console.ReadLine（）;         }