NGUI position and Position . i need use NGUITools.AddChild to create more object

if(Input.GetKeyDown(KeyCode.Q) )
{

		GameObject Clone = NGUITools.AddChild(test, record_ins);

		Clone.transform.position = new Vector3(myposition.position.x,myposition.position.y,0);

	}

then i try this
Vector3 temp = test.transform.localPosition;
temp.y = test.transform.position.y - 2;
test.transform.localPosition = temp;
when i create it, can create first . but second、thrid there position always print(0,0,0)
i need create new one under one.
sorry, this description and my english is not good. can someone to teach me. thanks.

I found a wrong. I use wrong algorithm.
so

public GameObject record_ins;
public GameObject position;
private float qwer;

Void Update()
{

Vector3 temp = myposition.localPosition;
temp.y = myposition.position.y - qwer;
myposition.transform.localPosition = temp;

if(Input.GetKeyDown(KeyCode.Q) )
{

		GameObject Clone = NGUITools.AddChild(test, record_ins);

		Clone.transform.position = new Vector3(myposition.position.x,myposition.position.y,0);
		qwer = qwer + 82;
	}

}

it’s work .