def haushaltsgröße_hh(hh_id: IntSeries) -> IntSeries:
"""Count persons in households.
Parameters
----------
hh_id
See basic input variable :ref:`hh_id <hh_id>`.
Returns
-------
IntSeries with the number of persons in household per household.
"""
return hh_id.groupby(hh_id).size()
def tax_unit_share(tu_id: IntSeries, haushaltsgröße: IntSeries) -> FloatSeries:
"""Calculate the share of tax units in household.
Parameters
----------
tu_id
See basic input variable :ref:`tu_id <tu_id>`.
haushaltsgröße
See :func:`haushaltsgröße`.
Returns
-------
"""
return tu_id.groupby(tu_id).transform("count") / haushaltsgröße
