Calculate the standard deviation of a list of values
    @param values: list(float)
    @param average:
    @return:

def calc_deviation(values, average):
    """
    Calculate the standard deviation of a list of values
    @param values: list(float)
    @param average:
    @return:
    """
    size = len(values)
    if size < 2:
        return 0
    calc_sum = 0.0

    for number in range(0, size):
        calc_sum += math.sqrt((values[number] - average) ** 2)
    return math.sqrt((1.0 / (size - 1)) * (calc_sum / size))