How to make script remember a counter and display an ad every 5th time?

I am finishing up a project for my university and I need to add a monetization method. I stopped at Interstitials from AdMob that will be displayed whenever the GameOver screen appears. My problem is that I want them to appear on every fifth appearance of this GameOver screen and so far I haven’t managed to make anything work. The interstitial appears ever time. Another problem that may affect this is that the script restarts every time I press Restart, so the ad counter won’t really work. Here is my code and I hope someone can assist!

Thank you!

public class GameOver: MonoBehaviour {

    static int loadCount = 0;

    private InterstitialAd interstitial;
    public GameObject gameOverScreen;


    bool gameOver;

    // Use this for initialization
    void Start () {
        FindObjectOfType<PlayerController>().OnPlayerDeath += OnGameOver;
        this.RequestInterstitial();

    }

    // Update is called once per frame
    public void Update () 
        if (gameOver)
        {
            if (Input.GetKeyDown (KeyCode.Space))
            {
                SceneManager.LoadScene(1);
            }
        }
    }

    private void RequestInterstitial()

    {
#if UNITY_ANDROID
        string adUnitId = "ca-app-pub-3940256099942544/1033173712";
#elif UNITY_IPHONE
        string adUnitId = "ca-app-pub-3940256099942544/4411468910";
#else
        string adUnitId = "unexpected_platform";
#endif

        // Initialize an InterstitialAd.
        interstitial = new InterstitialAd(adUnitId);

        AdRequest request = new AdRequest.Builder().Build();
        // Load the interstitial with the request.
        interstitial.LoadAd(request);
    }

    private void AdDisplay()
    {
        if (interstitial.IsLoaded())
        {
            interstitial.Show();
        }
    }

    void OnGameOver()
    {

        gameOverScreen.SetActive (true);
        kmHighscore.text = GetScore().ToString("F0");

        gameOver = true;
        if (loadCount % 5 == 0) 
        {
            AdDisplay();
        }
        loadCount++;
    }
}

Try to save float with


PlayerPrefs.SetFloat(“name of variable”, value of variable);
Eg. (“loadCount”,5); or (“loadCount”, loadCount) ;
PlayerPrefs.Save();


And get float with


float newcount= PlayerPrefs.GetFloat(“loadCount”,newcount);


And then compare value of newcount


if(newcount == 5)
{
//loadAD
}