How to spawn PowerUp only once every 100 points ?

Hi. I have problem with spawning PowerUp every 100 points. PowerUp not give points, just give speed to ball for 3 secs, and it must spawn only once per 100 points. And I dont have idea how to do this spawning only once every 100 points. Sorry for my english, I’m just starting to learn this language.

this is my code :

using UnityEngine;

using System.Collections;

namespace Ball{

public class BallPhysic : MonoBehaviour {
	

	private Vector3 ballPosition;

	public GameObject playerObject;
	public GameObject Terrain;
	public Transform SpeedUpPrefab;
	bool SpeedUpActive = true;

	float TerrainX, TerrainZ, BlockWidth;
	
	// Use this for initialization
	void Start () 
	{

		TerrainX = Terrain.collider.bounds.size.x;
		TerrainZ = Terrain.collider.bounds.size.z;
		BlockWidth = playerObject.transform.localScale.y;

		ballIsActive = false;
	
//		rigidbody.velocity = new Vector3(0f, 0f, -Speed);
		
		ballPosition = gameObject.transform.position;
		
	}

	void CreateNewSpeedUp()
	{

		var SpeedUp = Instantiate (SpeedUpPrefab);
		SpeedUp.name = "SpeedUp";
	}

	IEnumerator OnTriggerEnter(Collider collider)
	{
		
		if(collider.gameObject.name =="SpeedUp") 
		{
			Destroy(collider.gameObject);
			//setSpeed(1.75f);
			//setVelocityBall();
		
			yield return new WaitForSeconds(3f);

			//SetNormalSpeed();
			//setVelocityBall();
		}
		
	}

	// Update is called once per frame
	void Update () {
	
		if (Score % 100 == 0 && SpeedUpActive) 
		{

			CreateNewSpeedUp();
			SpeedUpActive=false;
		}

	}
}

}

Create a new prefab that has an OnTriggerEnter function that makes it collectable by the player and instatiate that prefab using Instatiate. I am not sure where you want to create it.
Also it is better to set the SpeedUpActive false when you collect the instatiated object , because for as long as you have points%100 = 0 you will still be creating prefabs.