JQuery :: Selector Only Selects One (last) Of Matched Classes

I have code to add a row dynamically to a form in my page when an element with class 'addRow' is clicked. The tables (2 tables in one page) that I want to add the row to have class 'tableAddRow'. The tables are contained in a form. But for some strange reason the code only adds to the last matched table in the page. I tried using the $.each selector but nothing works.

Here is the code:
$(document).ready(function(){
$(".addRow").click(function(){
$(".tableAddRow tr:last").clone().insertAfter(".tableAddRow tr:last");
$(".tableAddRow tr:last input").val("");
});
});