def irr2apr(irr):
    """ Turns IRR into APR

        IRR is not the same thing as APR, Annual Percentage Rate. The
        IRR is per time period, i.e. 1 month, and the APR is per year,
        and note that that you need to raise to the power of 12, not
        mutliply by 12.
    """
    return 100 * (pow(1 + irr / (12 * 100.0), 12) - 1)
