vector3 current postion +1

hi i am nooba t this to start! anyways i am making a pong game to practice my scripting and i want it so that when player presses up the object to move up on the y axis +1. so i had this:

using UnityEngine;
using System.Collections;

public class bat_right : MonoBehaviour {

public float bat_rightSpeed;

// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () 
{

    float amntToMove = Input.GetAxis("bat_right") * bat_rightSpeed * Time.deltaTime;
    transform.position = new Vector3(

}

}

i want it to not change x and z but to take current y postion and add one unit. is this possible and how would i do it?

thanks in advance

Try

float amntToMove = Input.GetAxis("bat_right") * bat_rightSpeed * Time.deltaTime;
transform.position += Vector3.up * amntToMove;