save table to folder in appropriate files
        NOTE - ONLY APPEND AT THIS STAGE - THEN USE DATABASE

def save(self, file_tag='2016', add_header='N'):
        """
        save table to folder in appropriate files
        NOTE - ONLY APPEND AT THIS STAGE - THEN USE DATABASE
        """
        fname = self.get_filename(file_tag)
        with open(fname, 'a') as f:
            if add_header == 'Y':
                f.write(self.format_hdr())
                
            for e in self.table: 
                    f.write(e.format_csv())