private void InsertInOrder(CarListEntry e)
    {
        //create the current and previous object references for the linked list
        CarListEntry current = head;
        CarListEntry previous = null;

        //if the entry is empty then return nothing
        if (e == null)
        {
            return;
        }

        //if the list is empty, then have the head aand tail refer to the
        //element being added, and it's next reference to be null.  Return
        //Nothing
        if (head == null)
        {
            head = e;
            tail = e;
            e.Next = null;
            return;
        }
        //traverse through the list.  If the current item is larger than the
        //item we are adding (in terms of year) then make the previous item
        //refer to the current item and the current refer to the item after it
        while(current.Next != null && (current.Data.Year > e.Data.Year))
        {
            previous = current;
            current = current.Next;
        }

        //if the previous items happens to be null, then it is the first
        //element.  Update it as the head.
        if (previous == null)
        {
            e.Next = head;
            head = e;
        }

        else
        {
            //if the item after the previous is empty then it is the tail
            //update the tail in the list.
            if (previous.Next == null)
            {
                tail.Next = e;
                tail = e;
            }

            //if it is in the middle, have the item after the previous be
            //the updated items new 'next' reference, and have the item
            //before it equal the item to be added
            e.Next = previous.Next;
            previous.Next = e;
        }
    }