def merge_stats(self, other_col_counters):
        """
        Merge statistics from a different column stats counter in to this one.
        Parameters
        ----------
        other_column_counters: Other col_stat_counter to marge in to this one.
        """
        for column_name, _ in self._column_stats.items():
            self._column_stats[column_name] = self._column_stats[column_name] \
                .mergeStats(other_col_counters._column_stats[column_name])
        return self