Count remaining items in order to calculate percentages
<p>I have a page where a user has to drag items from an area elsewhere on a screen.</p>

<p>When all items are dragged out -- 100% task is accomplished.</p>

<p>I would like to calculate what % of the task is accomplished on each drag and drop (when an items is dragged out of gray area).</p>

<p>How do I count remaining items within an area?</p>

<p>How do I convert into percentages?</p>

<p>Shall I calculate what each item's worth in terms of % on page load and then subtract?</p>
