Script to have a deltatime and timescale independent to Time.deltaTime in Unity

UNITY GameTime.cs

using UnityEngine;
using System.Collections;

public class GameTime : MonoBehaviour {
	public static GameTime manager;
	
	public float timeScale = 1;
	float elapsedTime;
	public static float deltaTime;
	
	void Awake(){
    manager = this;
	}
	
	// Update is called once per frame
	void Update () {
		deltaTime = Time.deltaTime * timeScale;

		if(Input.GetKeyDown(KeyCode.KeypadPlus)){
			timeScale += 0.5f;
		}
		if(Input.GetKeyDown(KeyCode.KeypadMinus)){
			timeScale -= 0.5f;
		}
    if(Input.GetKeyUp(KeyCode.Y)){
      timeScale = (timeScale == 1f) ? 10f : 1f;
    }
		
		elapsedTime += Time.deltaTime * timeScale;
		elapsedTime = Mathf.Max(0, elapsedTime);
	}
}