Populate spm_unit_pre_subsidy_childcare_expenses from CPS ASEC

MP exported spm_unit_pre_subsidy_childcare_expenses as zero, so the national
childcare target (spm_unit_capped_work_childcare_expenses) read $0 against a
~$348B baseline. eCPS reads the input directly from the CPS ASEC SPM field
SPM_CHILDCAREXPNS.

Wire SPM_CHILDCAREXPNS -> spm_unit_pre_subsidy_childcare_expenses through the
same path as spm_unit_energy_subsidy: the PERSON_VARIABLES rename, the
nonnegative and zero-default value-column lists, and the spm_unit source-column
aggregation. PolicyEngine computes spm_unit_capped_work_childcare_expenses from
this input, so the computed variable is not exported (the frozen export contract
deliberately excludes it as formula-owned). Mirror the existing energy-subsidy
mapping and entity-aggregation tests.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: MaxGhenis

src/microplex_us/data_sources/cps.py

@@ -117,6 +117,9 @@
     "WICYN": "_receives_wic",
     "SPM_CAPHOUSESUB": "_spm_capped_housing_subsidy",
     "SPM_ENGVAL": "spm_unit_energy_subsidy",
+    # Capped work childcare expenses are a PolicyEngine-computed variable
+    # (derived from this pre-subsidy input), so only the input is exported.
+    "SPM_CHILDCAREXPNS": "spm_unit_pre_subsidy_childcare_expenses",
     # Person relationship-to-householder code (eCPS cps.py:190-195, :1219).
     # Codes 43/44/46/47 mark an unmarried partner of the household head.
     "PERRP": "_person_relationship_to_householder",
@@ -200,6 +203,7 @@
     "social_security_survivors",
     "social_security_dependents",
     "spm_unit_energy_subsidy",
+    "spm_unit_pre_subsidy_childcare_expenses",
 )
 
 PERSON_ZERO_DEFAULT_VALUE_COLUMNS = (
@@ -216,6 +220,7 @@
     "social_security_survivors",
     "social_security_dependents",
     "spm_unit_energy_subsidy",
+    "spm_unit_pre_subsidy_childcare_expenses",
 )
 
 PERSON_CACHE_REQUIRED_COLUMNS = (

src/microplex_us/pipelines/us.py

@@ -9887,6 +9887,7 @@ def _attach_spm_unit_source_columns(
             "takes_up_snap_if_eligible": "max",
             "takes_up_tanf_if_eligible": "max",
             "spm_unit_energy_subsidy": "first",
+            "spm_unit_pre_subsidy_childcare_expenses": "first",
         }
         aggregations = {
             column: aggregation

tests/pipelines/test_us.py

@@ -1014,6 +1014,7 @@ def test_build_policyengine_entity_tables_preserves_spm_source_inputs(
                 "takes_up_housing_assistance_if_eligible": [False, True, False],
                 "takes_up_snap_if_eligible": [False, True, False],
                 "spm_unit_energy_subsidy": [90.0, 90.0, 0.0],
+                "spm_unit_pre_subsidy_childcare_expenses": [1500.0, 1500.0, 0.0],
             }
         )
 
@@ -1028,6 +1029,10 @@ def test_build_policyengine_entity_tables_preserves_spm_source_inputs(
         ]
         assert spm_units["takes_up_snap_if_eligible"].tolist() == [True, False]
         assert spm_units["spm_unit_energy_subsidy"].tolist() == [90.0, 0.0]
+        assert spm_units["spm_unit_pre_subsidy_childcare_expenses"].tolist() == [
+            1500.0,
+            0.0,
+        ]
 
     def test_build_policyengine_entity_tables_adds_deterministic_snap_takeup(
         self,

tests/test_cps_source_provider.py

@@ -447,6 +447,7 @@ def test_load_cps_asec_derives_policyengine_value_inputs(tmp_path):
             "WICYN": [1, 2],
             "SPM_CAPHOUSESUB": [700, 0],
             "SPM_ENGVAL": [90, -1],
+            "SPM_CHILDCAREXPNS": [1500, -1],
             "PHIP_VAL": [900, -1],
             "POTC_VAL": [120, -1],
             "PMED_VAL": [450, -1],
@@ -474,6 +475,7 @@ def test_load_cps_asec_derives_policyengine_value_inputs(tmp_path):
     assert persons["receives_housing_assistance"].tolist() == [True, False]
     assert persons["takes_up_housing_assistance_if_eligible"].tolist() == [True, False]
     assert persons["spm_unit_energy_subsidy"].tolist() == [90, 0]
+    assert persons["spm_unit_pre_subsidy_childcare_expenses"].tolist() == [1500, 0]
     assert persons["health_insurance_premiums_without_medicare_part_b"].tolist() == [900, 0]
     assert persons["over_the_counter_health_expenses"].tolist() == [120, 0]
     assert persons["other_medical_expenses"].tolist() == [450, 0]