C#字典（dictionary）中的旧value被新value替换了

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.Text.RegularExpressions;
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            DirectoryInfo dir = new DirectoryInfo(".");//new DirectoryInfo(".") 
            FileInfo[] inf = dir.GetFiles();
            StreamReader rd;//用于打开“A5E”文件
            Storage stor = new Storage();//实例化
            foreach (FileInfo finf in inf)
            {
                if (finf.Extension.Equals(".A5E")) //假如扩展名为“.A5E”
                {
                    string path = finf.Name;
                    rd = File.OpenText(path);
                    string s = rd.ReadToEnd();
                    string[] sArray = s.Split("&"); // split the string into seperate strings using &
                    Storage.counter = 0;
                    for (int i = 0; i < sArray.Length; i++)//i是区分按照& split分开的部分
                    {
                        if (i % 2 == 1)
                        {
                            string[] lineArray = sArray[i].Split("\n"); //利用正则表达式将字符串中的数字提取出来分别保存在小数数组中                          
                            for (int ii = 7; ii < (lineArray.Length - 3); ii++) //ii是为了区分everyline of reinforcement layers
                            {
                                Storage.counter++;
                                MatchCollection vMatchs = Regex.Matches(lineArray[ii], @"((-?\d+)(\.\d+)?)");//读取出lineArray中的小数，并存在数组中
                                double[] vDouble = new double[vMatchs.Count];
                                for (int j = 0; j < vMatchs.Count; j++)//j是为了迭代读取出存储在vMatch中的每一行的小数
                                {
                                    vDouble[j] = double.Parse(vMatchs[j].Value);//store the number of the line into vInts array
                                }
                                stor.NS = vDouble[0];
                                stor.averageStress = vDouble[4];
                                Storage.Dic.Add(Storage.counter, stor);/////出现了大大的问题，字典中的旧值被新值覆盖了
                            }
                        }
                    }
                }
            }
        }
    }
    public class Storage
    {
        public static int counter = 0;//用于对A5E中的字典进行计数（key）
        public double NS
        { get; set; }
        public double averageStress
        { get; set; }
        public static SortedDictionary<int, Storage> Dic = new SortedDictionary<int, Storage>();
    }
}