Fix WA property tax exemption crash for households outside Washington

changelog.d/fix-wa-pte-county-lookup.fixed.md

@@ -0,0 +1 @@
+Stop the Washington senior and disabled property tax exemption from crashing simulations that include households outside Washington or with an unknown county.

policyengine_us/tests/policy/baseline/gov/states/wa/dor/property_tax_exemption/senior_disabled/wa_pte_income_eligible.yaml

@@ -241,3 +241,66 @@
     # CDI = 60,000 + 30,000 = 90,000 > King 2024 T3 ($84,000) -> ineligible.
     # Without the cotenant amount the tax unit would have qualified for Tier 3.
     wa_pte_income_eligible: false
+
+- name: Case 12, out-of-state and unknown-county households in one simulation with a King County household.
+  # defined_for masks the output but the formula still runs over every
+  # household in the simulation. Before the county guard, the South Dakota
+  # county and the UNKNOWN county reached the Washington county-keyed
+  # thresholds and raised ParameterNotFoundError.
+  period: 2024
+  input:
+    people:
+      person1:
+        age: 70
+      person2:
+        age: 70
+      person3:
+        age: 70
+      person4:
+        age: 70
+    tax_units:
+      tax_unit1:
+        members: [person1]
+        adjusted_gross_income: 84_000
+      tax_unit2:
+        members: [person2]
+        adjusted_gross_income: 84_000
+      tax_unit3:
+        members: [person3]
+        adjusted_gross_income: 41_000
+      tax_unit4:
+        members: [person4]
+        adjusted_gross_income: 41_001
+    spm_units:
+      spm_unit1:
+        members: [person1]
+      spm_unit2:
+        members: [person2]
+      spm_unit3:
+        members: [person3]
+      spm_unit4:
+        members: [person4]
+    households:
+      household1:
+        members: [person1]
+        state_code: WA
+        county: KING_COUNTY_WA
+      household2:
+        members: [person2]
+        state_code: SD
+        county: MARSHALL_COUNTY_SD
+      household3:
+        members: [person3]
+        state_code: WA
+        county: UNKNOWN
+      household4:
+        members: [person4]
+        state_code: WA
+        county: UNKNOWN
+  output:
+    # household1: King 2024 T3 = $84,000; income at threshold -> eligible.
+    # household2: South Dakota; defined_for zeroes the result.
+    # household3: UNKNOWN county falls back to Adams 2024 T3 = $41,000;
+    #   income at threshold -> eligible.
+    # household4: $41,001 > Adams T3 -> ineligible (King T3 would admit it).
+    wa_pte_income_eligible: [true, false, true, false]

policyengine_us/tests/policy/baseline/gov/states/wa/dor/property_tax_exemption/senior_disabled/wa_pte_tier.yaml

@@ -317,3 +317,58 @@
     # Completes the Tier 2 boundary triple together with Case 13 (T2-1) and
     # Case 2 (at T2).
     wa_pte_tier: 3
+
+- name: Case 15, 2027 out-of-state and unknown-county households in one simulation with a King County household.
+  # defined_for masks the output but the formula still runs over every
+  # household in the simulation. Before the county guard, the South Dakota
+  # county and the UNKNOWN county reached the Washington county-keyed
+  # thresholds and raised ParameterNotFoundError.
+  period: 2027
+  input:
+    people:
+      person1:
+        age: 70
+      person2:
+        age: 70
+      person3:
+        age: 70
+    tax_units:
+      tax_unit1:
+        members: [person1]
+        adjusted_gross_income: 83_500
+        filing_status: SINGLE
+      tax_unit2:
+        members: [person2]
+        adjusted_gross_income: 83_500
+        filing_status: SINGLE
+      tax_unit3:
+        members: [person3]
+        adjusted_gross_income: 52_500
+        filing_status: SINGLE
+    spm_units:
+      spm_unit1:
+        members: [person1]
+      spm_unit2:
+        members: [person2]
+      spm_unit3:
+        members: [person3]
+    households:
+      household1:
+        members: [person1]
+        state_code: WA
+        county: KING_COUNTY_WA
+      household2:
+        members: [person2]
+        state_code: SD
+        county: MARSHALL_COUNTY_SD
+      household3:
+        members: [person3]
+        state_code: WA
+        county: UNKNOWN
+  output:
+    # 2027 CDI = AGI - max(0, $7,500 single standard deduction).
+    # household1: CDI = 83,500 - 7,500 = 76,000 = King 2027 T1 -> Tier 1.
+    # household2: South Dakota; defined_for zeroes the result.
+    # household3: CDI = 52,500 - 7,500 = 45,000. UNKNOWN county falls back
+    #   to Adams 2027: T1 $42,000 < 45,000 <= T2 $49,000 -> Tier 2.
+    wa_pte_tier: [1, 0, 2]

policyengine_us/tests/policy/baseline/gov/states/wa/dor/property_tax_exemption/senior_disabled/wa_senior_disabled_property_tax_exemption.yaml

@@ -491,3 +491,86 @@
     # exemption = tier_3_exempt_share * real_estate_taxes
     #           = 0.45 * 5,000 = 2,250
     wa_senior_disabled_property_tax_exemption: 2_250
+
+- name: Case 19, 2026 Washington and South Dakota households in one simulation.
+  # Reproduces the full-population crash: defined_for masks the output but
+  # the tier lookup still runs over the South Dakota household, whose county
+  # is not a key of the Washington county thresholds.
+  period: 2026
+  input:
+    people:
+      person1:
+        age: 70
+        real_estate_taxes: 6_000
+        assessed_property_value: 700_000
+      person2:
+        age: 70
+        real_estate_taxes: 6_000
+        assessed_property_value: 700_000
+    tax_units:
+      tax_unit1:
+        members: [person1]
+        adjusted_gross_income: 40_000
+        filing_status: SINGLE
+      tax_unit2:
+        members: [person2]
+        adjusted_gross_income: 40_000
+        filing_status: SINGLE
+    spm_units:
+      spm_unit1:
+        members: [person1]
+      spm_unit2:
+        members: [person2]
+    households:
+      household1:
+        members: [person1]
+        state_code: WA
+        county: KING_COUNTY_WA
+      household2:
+        members: [person2]
+        state_code: SD
+        county: MARSHALL_COUNTY_SD
+  output:
+    # household1 is Case 16's household: 4,320.
+    # household2 is in South Dakota: 0.
+    wa_senior_disabled_property_tax_exemption: [4_320, 0]
+
+- name: Case 20, 2027 Washington and South Dakota households in one simulation.
+  period: 2027
+  input:
+    people:
+      person1:
+        age: 70
+        real_estate_taxes: 6_000
+        assessed_property_value: 700_000
+      person2:
+        age: 70
+        real_estate_taxes: 6_000
+        assessed_property_value: 700_000
+    tax_units:
+      tax_unit1:
+        members: [person1]
+        adjusted_gross_income: 40_000
+        filing_status: SINGLE
+      tax_unit2:
+        members: [person2]
+        adjusted_gross_income: 40_000
+        filing_status: SINGLE
+    spm_units:
+      spm_unit1:
+        members: [person1]
+      spm_unit2:
+        members: [person2]
+    households:
+      household1:
+        members: [person1]
+        state_code: WA
+        county: KING_COUNTY_WA
+      household2:
+        members: [person2]
+        state_code: SD
+        county: MARSHALL_COUNTY_SD
+  output:
+    # household1 is Case 17's household: 5,340.
+    # household2 is in South Dakota: 0.
+    wa_senior_disabled_property_tax_exemption: [5_340, 0]

policyengine_us/variables/gov/states/wa/dor/property_tax_exemption/senior_disabled/income/wa_pte_income_eligible.py

@@ -15,7 +15,15 @@ class wa_pte_income_eligible(Variable):
 
     def formula(tax_unit, period, parameters):
         income = tax_unit("wa_pte_combined_disposable_income", period)
+        # defined_for masks the output but does not stop the formula from
+        # running over every household, and the thresholds are keyed by
+        # Washington county only. Households outside Washington, or with an
+        # UNKNOWN county, are looked up under Adams County (the county the
+        # model assigns a Washington household that gives none) so the lookup
+        # cannot raise ParameterNotFoundError.
         county = tax_unit.household("county_str", period)
+        in_wa = tax_unit.household("state_code_str", period) == "WA"
+        county = where(in_wa & (county != "UNKNOWN"), county, "ADAMS_COUNTY_WA")
         p = parameters(
             period
         ).gov.states.wa.dor.property_tax_exemption.senior_disabled.income.thresholds

policyengine_us/variables/gov/states/wa/dor/property_tax_exemption/senior_disabled/income/wa_pte_tier.py

@@ -15,7 +15,15 @@ class wa_pte_tier(Variable):
 
     def formula(tax_unit, period, parameters):
         income = tax_unit("wa_pte_combined_disposable_income", period)
+        # defined_for masks the output but does not stop the formula from
+        # running over every household, and the thresholds are keyed by
+        # Washington county only. Households outside Washington, or with an
+        # UNKNOWN county, are looked up under Adams County (the county the
+        # model assigns a Washington household that gives none) so the lookup
+        # cannot raise ParameterNotFoundError.
         county = tax_unit.household("county_str", period)
+        in_wa = tax_unit.household("state_code_str", period) == "WA"
+        county = where(in_wa & (county != "UNKNOWN"), county, "ADAMS_COUNTY_WA")
         p = parameters(
             period
         ).gov.states.wa.dor.property_tax_exemption.senior_disabled.income.thresholds