def find_diff_of_numbers(stat1, stat2):
    """
    Finds the difference between two stats. If there is no difference, returns
    "unchanged". For ints/floats, returns stat1 - stat2.

    :param stat1: the first statistical input
    :type stat1: Union[int, float]
    :param stat2: the second statistical input
    :type stat2: Union[int, float]
    :return: the difference of the stats
    """
    diff = "unchanged"
    if stat1 is None and stat2 is None:
        pass
    elif stat1 is None or stat2 is None:
        diff = [stat1, stat2]
    elif stat1 != stat2:
        diff = stat1 - stat2
    return diff