jQuery - getting custom attribute from selected option

Given the following:

<select id="location">
    <option value="a" myTag="123">My option</option>
    <option value="b" myTag="456">My other option</option>
</select>

<input type="hidden" id="setMyTag" />

<script>
    $(function() {
        $("#location").change(function(){
            var element = $(this);
            var myTag = element.attr("myTag");

            $('#setMyTag').val(myTag);
        });
    });
</script>

That does not work...
What do I need to do to get the value of the hidden field updated to the value of myTag when the select is changed. I'm assuming I need to do something about getting the currently selected value...?