def reg_tap_cim_to_gld(step, step_voltage_increment):
    """

    :param step: CIM setting of voltage regulator, which is a
                    multiplier of nominal voltage, e.g. 1.0125.

    :param step_voltage_increment: voltage step as multiplier of nominal
                                   voltage, e.g. 0.625

    :return: tap position in GridLAB-D speak, e.g. 10 or -2
    """

    return round((step - 1) * 100 / step_voltage_increment)