# Global helper functions
def truncate(n, decimals=2):
    """Truncate a float to a particular number of decimals."""
    assert decimals > 0 and decimals < 10, "Decimals is weird"
    multiplier = 10 ** decimals
    return int(n * multiplier) / multiplier

def format_rate(rate):
    """Format a multiplier nee rate to look nice."""
    if rate >= 1.0:
        return format_rate(rate - 1.0)
    else:
        return "{:<}%".format(round(rate * 100, 3))

def convert_rate_to_multiplier(rate):
    return 1.0 + (rate / 100)