def format_percentage(val: float, suffix: str = ' %') -> str:
    """
    Formats a percentage value (0.0 - 1.0) in the standardized way.
    Returned value has a constant width and a trailing '%' sign.

    Args:
        val: Percentage value to be formatted.
        suffix: String to be appended to the result.

    Returns:
        Formatted percentage value with a constant width and trailing '%' sign.

    Examples:
        >>> print(format_percentage(0.359))
        str(' 36 %')

        >>> print(format_percentage(1.1))
        str('110 %')
    """

    return f'{round(val * 100): >3d}{suffix}'