def inserted_hs_indices(self):
        """list of int index of each inserted subtotal for the dimension.

        Each value represents the position of a subtotal in the interleaved
        sequence of elements and subtotals items.
        """
        # ---don't do H&S insertions for CA and MR subvar dimensions---
        if self.dimension_type in DT.ARRAY_TYPES:
            return []

        return [
            idx
            for idx, item in enumerate(
                self._iter_interleaved_items(self.valid_elements)
            )
            if item.is_insertion
        ]