Serialization creates file while returning nothing

I'm trying to achieve a persistent leader scoreboard with the help of serialization. At first I kept close to the Unity tutorial, but had to wander off after a while to actually make those functions work to my liking and for my purpose.

Here are the scripts
loadHighscore.cs

 using UnityEngine;
 using System.Collections;
 using System;
 using System.Runtime.Serialization.Formatters.Binary;
 using System.IO;
 
 public class loadHighScore : MonoBehaviour {
 
    
     int highScoreFinal;
     string playerName;
 
     public PlayerData playerData;
 
     void Start () {
 
         LoadFromFile();
         //print(playerData.playerName);
         //print(playerData.playerScore);
 
         //Debug.Log(playerData.playerName.ToString());
         //Debug.Log(playerData.playerScore.ToString());
     }
 
 
     public void LoadFromFile()
     {
         if (File.Exists(Application.persistentDataPath + "/highScore.dat"))
         {
             BinaryFormatter bf = new BinaryFormatter();
             FileStream file = File.Open(Application.persistentDataPath + "/highScore.dat", FileMode.Open);
             PlayerData data = (PlayerData)bf.Deserialize(file);
 
             file.Close();
 
             playerName = data.playerName;
             highScoreFinal = data.playerScore;          
         }
     }
 }
 

highScoreCounter.cs

 using UnityEngine;
 using System.Collections;
 using System;
 using System.Runtime.Serialization.Formatters.Binary;
 using System.IO;
 
 public class highscoreCounter : MonoBehaviour
 {
 
     public static highscoreCounter control;
     
     int highScoreFinal;
     string playerName;    
 
     
     void Update()
     {
         highScoreFinal = GetComponent<highscoreCalculator>().highScoreFinal;
         playerName = GameObject.Find("LevelFinisher").GetComponent<finishLevel>().newPlayerName;        
     }
     public void SaveToFile()
     {
         BinaryFormatter bf = new BinaryFormatter();
         FileStream file = File.Create(Application.persistentDataPath + "/highScore.dat");
 
         PlayerData data = new PlayerData();
         data.playerName = playerName;
         data.playerScore = highScoreFinal;
 
         bf.Serialize(file, data);
         file.Close();
     }
 }   

PlayerData.cs

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
 using System;
 
 [Serializable]
 public class PlayerData
 {
     public string playerName;
     public int playerScore;
 }
 
 public class PlayerDatabase
 {
     public List<PlayerData> list = new List<PlayerData>();
 }
 

So, what is going on: I am having troubles filling the *.dat file. What happens is that as soon as the game ends and I enter my string as well as my highscore, it's fed into the file and saved. The file continually grows bigger.

When I try to load the values to check if they are actually saved, it will return me null for the strings, and 0 for the integers. I cannot tell whats going on, and I would really appreciate any tips.

ps: Yes, I could make this into saving a xml to check, or use PlayerPrefs, but I really want to learn how to work with serialization.....

Thanks!