def cb_round(series, base=5, sig_dec=0):
    """ Returns the pandas series (or column) with values rounded per the
            custom base value

        Args:
            series (pd.Series): data to be rounded
            base (float): base value to which data should be rounded (may be
                decimal)
            sig_dec (int): number of significant decimals for the
                custom-rounded value
    """
    if not base >= 0.01:
        raise ValueError(f"cannot round with base {base}."
                         + "cb_round designed for base >= 0.01."
                         )
    result = series.apply(lambda x: round(base * round(float(x)/base), sig_dec))
    return result