def New_Dataframe(old_df,indicator_name):
    """ create a new dataframe that is composed of only one indicator
    
    Args:
    
        old_df (dataframe): general dataframe from which we extract the new one
        indicator_name (string): Name onf the indicator that will composed the new dataframe
        
    Returns:
    
        (dataframe): dataframe composed of only the chosen indicator
    
    """
    return old_df.loc[old_df.Indicator == indicator_name]