Forms :: Insert Same Date Into Column With Button

I have form with these info : customer (Table), EnterDate (Button) and customersub (subform), i want to enter date into Date column using form with button.

example

ID name sample date
1. John A ....
2. Michel B ....
3. Jack C .....

into like this

ID name sample date
1. John A 2/2/2014
2. Michel B 2/2/2014
3. Jack C 2/2/2014

I try this this sql. but the date only insert/update for avery row i was select.

Q: How i can make sure i put one date.. it will insert for every row just one click.

Private Sub EnterDate_Click()
CurrentDb.Execute "UPDATE Customer " & _
"SET Date='" & Me.insertdate & "'" & _
"WHERE ID= " & Me.Costumersub.Form.Recordset.Fields("ID")
End Sub