def to_csv(self, path, iamc_index=False, **kwargs):
        """Write timeseries data to a csv file

        Parameters
        ----------
        path: string
            file path
        iamc_index: bool, default False
            if True, use `['model', 'scenario', 'region', 'variable', 'unit']`;
            else, use all `data` columns
        """
        self._to_file_format(iamc_index).to_csv(path, index=False, **kwargs)