Fix TANF benefit cap across all 42 states

changelog_entry.yaml

@@ -0,0 +1,4 @@
+- bump: patch
+  changes:
+    fixed:
+      - Cap all state TANF benefit formulas to prevent negative countable income from inflating benefits above the payment standard. Fixes NC household size .sum() bug and adds min_() caps to 38 state programs (AL, AK, AR, AZ, CA, CO, CT, DC, FL, HI, IA, IL, IN, KS, LA, MA, MD, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TX, UT, VT, WV, WY). Previously, negative countable income could produce benefits exceeding $1M per household, inflating total TANF microsimulation from $9B target to $17.9T.

policyengine_us/tests/policy/baseline/gov/hhs/tanf/cash/tanf_negative_income_cap.yaml

@@ -0,0 +1,79 @@
+# Tests that TANF benefits are capped at the maximum payment amount,
+# even when countable income is negative.
+# This prevents the bug where negative income inflates benefits
+# beyond the payment standard (e.g., benefit = max - (-5M) = 5M+).
+
+- name: CA TANF benefit capped at max payment when countable income is negative.
+  period: 2023
+  input:
+    ca_tanf_eligible: true
+    ca_tanf_maximum_payment: 1_000
+    ca_tanf_countable_income_recipient: -5_000
+  output:
+    ca_tanf: 1_000
+
+- name: PA TANF benefit capped at max when countable income is negative.
+  period: 2025-01
+  input:
+    pa_tanf_eligible: true
+    pa_tanf_maximum_benefit: 500
+    pa_tanf_countable_income: -10_000
+  output:
+    pa_tanf: 500
+
+- name: NY TANF benefit capped at need standard when income is negative.
+  period: 2025-01
+  input:
+    ny_tanf_eligible: true
+    ny_tanf_need_standard: 800
+    ny_tanf_countable_income: -1_000
+  output:
+    ny_tanf: 800
+
+- name: FL TCA benefit capped at payment standard when income is negative.
+  period: 2025-01
+  input:
+    fl_tca_eligible: true
+    fl_tca_payment_standard: 300
+    fl_tca_countable_income: -50_000
+  output:
+    fl_tca: 300
+
+- name: NC TANF reduced need standard capped at need standard when income is negative.
+  period: 2025
+  input:
+    people:
+      person1:
+        age: 30
+    households:
+      household1:
+        members: [person1]
+        state_code: NC
+    spm_units:
+      spm_unit:
+        members: [person1]
+        nc_tanf_need_standard: 500
+        nc_tanf_countable_earned_income: -10_000
+        nc_tanf_countable_gross_unearned_income: 0
+  output:
+    nc_tanf_reduced_need_standard: 500
+
+- name: MN MFIP benefit capped at transitional standard when unearned is negative.
+  period: 2025-01
+  input:
+    mn_mfip_eligible: true
+    mn_mfip_transitional_standard: 600
+    mn_mfip_family_wage_level: 800
+    mn_mfip_countable_earned_income: 0
+    mn_mfip_countable_unearned_income: -100_000
+  output:
+    mn_mfip: 600
+
+- name: OH OWF benefit capped at payment standard when income is negative.
+  period: 2025-01
+  input:
+    oh_owf_eligible: true
+    oh_owf_payment_standard: 400
+    oh_owf_countable_income: -5_000
+  output:
+    oh_owf: 400

policyengine_us/variables/gov/states/ak/dpa/atap/ak_atap.py

@@ -36,8 +36,11 @@ def formula(spm_unit, period, parameters):
         # multiplied by (size 2 max payment / size 2 need standard)
         # The ratio uses fixed size-2 values, not the family's actual size
         income_deficit = max_(need_standard - countable_income, 0)
+        # Cap deficit at need standard to prevent negative income
+        # from inflating benefits above the maximum.
+        capped_deficit = min_(income_deficit, need_standard)
         size_2_max = p.payment.base
         # Per 7 AAC 45.525: ratable reduction formula always uses size-2 as base
         size_2_need = p.need_standard.amount["2"]
         ratable_reduction = size_2_max / size_2_need
-        return income_deficit * ratable_reduction
+        return capped_deficit * ratable_reduction

policyengine_us/variables/gov/states/al/dhs/tanf/al_tanf.py

@@ -13,4 +13,5 @@ class al_tanf(Variable):
     def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("al_tanf_payment_standard", period)
         countable_income = spm_unit("al_tanf_countable_income", period)
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/ar/dhs/tea/ar_tea.py

@@ -31,8 +31,10 @@ def formula(spm_unit, period, parameters):
 
         # When gross income >= trigger: payment is 50% of max (no subtraction)
         # When gross income < trigger: payment is max - countable income
+        below_trigger_benefit = max_(maximum_benefit - countable_income, 0)
+        capped_benefit = min_(below_trigger_benefit, maximum_benefit)
         return where(
             above_trigger,
             reduced_payment,
-            max_(maximum_benefit - countable_income, 0),
+            capped_benefit,
         )

policyengine_us/variables/gov/states/az/hhs/tanf/az_tanf.py

@@ -13,4 +13,7 @@ class az_tanf(Variable):
     def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("az_tanf_payment_standard", period)
         countable_income = spm_unit("az_tanf_countable_income", period)
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        # Cap benefit at payment standard to prevent negative income
+        # from inflating benefits above the maximum.
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/ca/cdss/tanf/cash/ca_tanf.py

@@ -25,4 +25,8 @@ def formula(spm_unit, period, parameters):
             eligible_people_based_on_immigration_status[mask]
             / spm_unit_size[mask]
         )
-        return prorated_fraction * max_(maximum_payment - countable_income, 0)
+        benefit = max_(maximum_payment - countable_income, 0)
+        # Cap benefit at maximum payment to prevent negative income
+        # from inflating benefits above the maximum.
+        capped_benefit = min_(benefit, maximum_payment)
+        return prorated_fraction * capped_benefit

policyengine_us/variables/gov/states/co/cdhs/tanf/co_tanf.py

@@ -19,4 +19,5 @@ def formula(spm_unit, period, parameters):
                 "co_tanf_countable_gross_unearned_income",
             ],
         )
-        return max_(grant_standard - income, 0)
+        benefit = max_(grant_standard - income, 0)
+        return min_(benefit, grant_standard)

policyengine_us/variables/gov/states/ct/dss/tfa/ct_tfa.py

@@ -18,7 +18,8 @@ def formula(spm_unit, period, parameters):
         countable_unearned_income = spm_unit(
             "ct_tfa_countable_unearned_income", period
         )
-        benefit_amount = max_(payment_standard - countable_unearned_income, 0)
+        raw_benefit = max_(payment_standard - countable_unearned_income, 0)
+        benefit_amount = min_(raw_benefit, payment_standard)
         # When gross earnings are >= 171% of FPG, reduce the benefit by 20%
         gross_earnings = add(spm_unit, period, ["tanf_gross_earned_income"])
         fpg = spm_unit("tanf_fpg", period)

policyengine_us/variables/gov/states/dc/dhs/tanf/dc_tanf.py

@@ -15,4 +15,5 @@ class dc_tanf(Variable):
     def formula(spm_unit, period, parameters):
         standard_payment = spm_unit("dc_tanf_standard_payment", period)
         countable_income = spm_unit("dc_tanf_countable_income", period)
-        return max_(standard_payment - countable_income, 0)
+        benefit = max_(standard_payment - countable_income, 0)
+        return min_(benefit, standard_payment)

policyengine_us/variables/gov/states/fl/dcf/tanf/fl_tca.py

@@ -19,4 +19,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit("fl_tca_countable_income", period)
 
         # Benefit = Payment Standard - Countable Income
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/hi/dhs/tanf/hi_tanf.py

@@ -17,4 +17,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit("hi_tanf_countable_income", period)
 
         # Benefit = SOA - countable income, floored at 0
-        return max_(maximum_benefit - countable_income, 0)
+        benefit = max_(maximum_benefit - countable_income, 0)
+        return min_(benefit, maximum_benefit)

policyengine_us/variables/gov/states/ia/dhs/fip/ia_fip.py

@@ -13,4 +13,5 @@ class ia_fip(Variable):
     def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("ia_fip_payment_standard", period)
         countable_income = spm_unit("ia_fip_countable_income", period)
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/il/dhs/tanf/il_tanf.py

@@ -17,4 +17,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit(
             "il_tanf_countable_income_for_grant_calculation", period
         )
-        return max_(payment_level - countable_income, 0)
+        benefit = max_(payment_level - countable_income, 0)
+        return min_(benefit, payment_level)

policyengine_us/variables/gov/states/in/fssa/tanf/in_tanf.py

@@ -18,4 +18,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit(
             "in_tanf_countable_income_for_payment", period
         )
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/ks/dcf/tanf/ks_tanf.py

@@ -18,4 +18,5 @@ def formula(spm_unit, period, parameters):
         # Benefit = Payment Standard - Countable Income
         maximum_benefit = spm_unit("ks_tanf_maximum_benefit", period)
         countable_income = spm_unit("ks_tanf_countable_income", period)
-        return max_(maximum_benefit - countable_income, 0)
+        benefit = max_(maximum_benefit - countable_income, 0)
+        return min_(benefit, maximum_benefit)

policyengine_us/variables/gov/states/la/dcfs/fitap/la_fitap.py

@@ -15,4 +15,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit("la_fitap_countable_income", period)
 
         # Benefit = flat grant minus countable income
-        return max_(flat_grant - countable_income, 0)
+        benefit = max_(flat_grant - countable_income, 0)
+        return min_(benefit, flat_grant)

policyengine_us/variables/gov/states/ma/dta/tcap/tafdc/payment/ma_tafdc_potential_main_benefit.py

@@ -15,4 +15,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit(
             "ma_tafdc_applicable_income_grant_amount", period
         )
-        return max_(0, payment_standard - countable_income)
+        benefit = max_(0, payment_standard - countable_income)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/md/tca/md_tca.py

@@ -13,4 +13,5 @@ class md_tca(Variable):
     def formula(spm_unit, period, parameters):
         grant_standard = spm_unit("md_tca_maximum_benefit", period)
         countable_income = spm_unit("md_tca_countable_income", period)
-        return max_(grant_standard - countable_income, 0)
+        benefit = max_(grant_standard - countable_income, 0)
+        return min_(benefit, grant_standard)

policyengine_us/variables/gov/states/mi/mdhhs/fip/mi_fip.py

@@ -27,4 +27,5 @@ def formula(spm_unit, period, parameters):
 
         # BEM 518: Minimum benefit requirement is $10 deficit
         # Negative benefits are set to 0
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/mn/dcyf/mfip/mn_mfip.py

@@ -28,4 +28,5 @@ def formula(spm_unit, period, parameters):
         # Step 2: Cap at transitional standard
         earned_based_benefit = min_(fwl_minus_earned, transitional_standard)
         # Step 3: Subtract countable unearned income, floor at zero
-        return max_(earned_based_benefit - countable_unearned, 0)
+        benefit = max_(earned_based_benefit - countable_unearned, 0)
+        return min_(benefit, transitional_standard)

policyengine_us/variables/gov/states/mo/dss/tanf/mo_tanf.py

@@ -17,5 +17,6 @@ def formula(spm_unit, period, parameters):
         maximum_benefit = spm_unit("mo_tanf_maximum_benefit", period)
         countable_income = spm_unit("mo_tanf_countable_income", period)
         benefit = max_(maximum_benefit - countable_income, 0)
+        capped_benefit = min_(benefit, maximum_benefit)
         p = parameters(period).gov.states.mo.dss.tanf
-        return where(benefit >= p.minimum_payment, benefit, 0)
+        return where(capped_benefit >= p.minimum_payment, capped_benefit, 0)

policyengine_us/variables/gov/states/ms/dhs/tanf/ms_tanf.py

@@ -16,4 +16,5 @@ class ms_tanf(Variable):
     def formula(spm_unit, period, parameters):
         maximum_benefit = spm_unit("ms_tanf_maximum_benefit", period)
         countable_income = spm_unit("ms_tanf_countable_income", period)
-        return max_(maximum_benefit - countable_income, 0)
+        benefit = max_(maximum_benefit - countable_income, 0)
+        return min_(benefit, maximum_benefit)

policyengine_us/variables/gov/states/mt/dhs/tanf/mt_tanf.py

@@ -16,4 +16,5 @@ class mt_tanf(Variable):
     def formula(spm_unit, period, parameters):
         standard_payment = spm_unit("mt_tanf_payment_standard", period)
         countable_income = spm_unit("mt_tanf_countable_income", period)
-        return max_(standard_payment - countable_income, 0)
+        benefit = max_(standard_payment - countable_income, 0)
+        return min_(benefit, standard_payment)

policyengine_us/variables/gov/states/nc/ncdhhs/tanf/nc_tanf_household_size.py

@@ -15,4 +15,4 @@ def formula(spm_unit, period, parameters):
         # Eligible members are those with no SSI income
         eligible_members = ssi_income <= 0
 
-        return eligible_members.sum()
+        return spm_unit.sum(eligible_members)

policyengine_us/variables/gov/states/nc/ncdhhs/tanf/nc_tanf_reduced_need_standard.py

@@ -20,4 +20,5 @@ def formula(spm_unit, period, parameters):
         )
         need_standard = spm_unit("nc_tanf_need_standard", period)
 
-        return max_(need_standard - income, 0)
+        reduced = max_(need_standard - income, 0)
+        return min_(reduced, need_standard)

policyengine_us/variables/gov/states/nd/dhs/tanf/nd_tanf.py

@@ -13,4 +13,5 @@ class nd_tanf(Variable):
     def formula(spm_unit, period, parameters):
         standard_of_need = spm_unit("nd_tanf_standard_of_need", period)
         countable_income = spm_unit("nd_tanf_countable_income", period)
-        return max_(standard_of_need - countable_income, 0)
+        benefit = max_(standard_of_need - countable_income, 0)
+        return min_(benefit, standard_of_need)

policyengine_us/variables/gov/states/ne/dhhs/adc/ne_adc.py

@@ -16,4 +16,5 @@ class ne_adc(Variable):
     def formula(spm_unit, period, parameters):
         maximum_benefit = spm_unit("ne_adc_maximum_benefit", period)
         unearned = add(spm_unit, period, ["tanf_gross_unearned_income"])
-        return max_(maximum_benefit - unearned, 0)
+        benefit = max_(maximum_benefit - unearned, 0)
+        return min_(benefit, maximum_benefit)

policyengine_us/variables/gov/states/nh/dhhs/fanf/nh_fanf.py

@@ -16,4 +16,5 @@ class nh_fanf(Variable):
     def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("nh_fanf_payment_standard", period)
         countable_income = spm_unit("nh_fanf_countable_income", period)
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/nj/njdhs/wfnj/nj_wfnj.py

@@ -15,4 +15,5 @@ class nj_wfnj(Variable):
     def formula(spm_unit, period, parameters):
         payment_levels = spm_unit("nj_wfnj_payment_levels", period)
         countable_income = spm_unit("nj_wfnj_countable_income", period)
-        return max_(payment_levels - countable_income, 0)
+        benefit = max_(payment_levels - countable_income, 0)
+        return min_(benefit, payment_levels)

policyengine_us/variables/gov/states/nm/hca/nm_works/nm_works.py

@@ -18,4 +18,5 @@ def formula(spm_unit, period, parameters):
         # Benefit = Payment Standard - Net Countable Income
         maximum_benefit = spm_unit("nm_works_maximum_benefit", period)
         countable_income = spm_unit("nm_works_countable_income", period)
-        return max_(maximum_benefit - countable_income, 0)
+        benefit = max_(maximum_benefit - countable_income, 0)
+        return min_(benefit, maximum_benefit)

policyengine_us/variables/gov/states/nv/dwss/tanf/nv_tanf.py

@@ -14,4 +14,7 @@ def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("nv_tanf_payment_standard", period)
         countable_income = spm_unit("nv_tanf_countable_income", period)
         # Benefit is payment standard minus countable income
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        # Cap benefit at payment standard to prevent negative income
+        # from inflating benefits above the maximum.
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/ny/otda/tanf/ny_tanf.py

@@ -12,4 +12,5 @@ class ny_tanf(Variable):
     def formula(spm_unit, period, parameters):
         need_standard = spm_unit("ny_tanf_need_standard", period)
         income = spm_unit("ny_tanf_countable_income", period)
-        return max_(need_standard - income, 0)
+        benefit = max_(need_standard - income, 0)
+        return min_(benefit, need_standard)

policyengine_us/variables/gov/states/oh/odjfs/owf/oh_owf.py

@@ -20,4 +20,5 @@ def formula(spm_unit, period, parameters):
         countable_income = spm_unit("oh_owf_countable_income", period)
 
         # Per OAC 5101:1-23-40: benefit = payment standard - countable income
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/ok/dhs/tanf/ok_tanf.py

@@ -20,6 +20,9 @@ def formula(spm_unit, period, parameters):
 
         # Per OAC 340:10-3-59: Benefit = Payment Standard - Countable Income
         benefit = max_(payment_standard - countable_income, 0)
+        capped_benefit = min_(benefit, payment_standard)
 
         # Per OAC 340:10-3-59: Minimum benefit is $10; if less, no payment issues
-        return where(benefit >= p.benefit.minimum_benefit, benefit, 0)
+        return where(
+            capped_benefit >= p.benefit.minimum_benefit, capped_benefit, 0
+        )

policyengine_us/variables/gov/states/or/odhs/tanf/or_tanf.py

@@ -18,8 +18,9 @@ def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("or_tanf_payment_standard", period)
         adjusted_income = spm_unit("or_tanf_adjusted_income", period)
         calculated_benefit = max_(payment_standard - adjusted_income, 0)
+        capped_benefit = min_(calculated_benefit, payment_standard)
         return where(
-            calculated_benefit >= p.minimum_benefit,
-            calculated_benefit,
+            capped_benefit >= p.minimum_benefit,
+            capped_benefit,
             0,
         )

policyengine_us/variables/gov/states/pa/dhs/tanf/pa_tanf.py

@@ -16,4 +16,7 @@ def formula(spm_unit, period, parameters):
         maximum_benefit = spm_unit("pa_tanf_maximum_benefit", period)
         countable_income = spm_unit("pa_tanf_countable_income", period)
 
-        return max_(maximum_benefit - countable_income, 0)
+        benefit = max_(maximum_benefit - countable_income, 0)
+        # Cap benefit at maximum to prevent negative income
+        # from inflating benefits above the maximum.
+        return min_(benefit, maximum_benefit)

policyengine_us/variables/gov/states/ri/dhs/works/ri_works.py

@@ -16,4 +16,5 @@ class ri_works(Variable):
     def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("ri_works_payment_standard", period)
         countable_income = spm_unit("ri_works_countable_income", period)
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/sc/tanf/sc_tanf.py

@@ -16,5 +16,8 @@ def formula(spm_unit, period, parameters):
         fpg = spm_unit("tanf_fpg", period)
         need_standard = fpg * p.income.need_standard.rate
         countable_income = spm_unit("sc_tanf_countable_income", period)
-        excess_income = need_standard - countable_income
-        return excess_income * p.payment.rate
+        excess_income = max_(need_standard - countable_income, 0)
+        benefit = excess_income * p.payment.rate
+        # Cap benefit at need standard to prevent negative income
+        # from inflating benefits above the maximum.
+        return min_(benefit, need_standard * p.payment.rate)

policyengine_us/variables/gov/states/sd/dss/tanf/sd_tanf.py

@@ -13,4 +13,5 @@ class sd_tanf(Variable):
     def formula(spm_unit, period, parameters):
         payment_standard = spm_unit("sd_tanf_payment_standard", period)
         countable_income = spm_unit("sd_tanf_countable_income", period)
-        return max_(payment_standard - countable_income, 0)
+        benefit = max_(payment_standard - countable_income, 0)
+        return min_(benefit, payment_standard)

policyengine_us/variables/gov/states/tx/tanf/tx_regular_tanf.py

@@ -22,6 +22,7 @@ def formula(spm_unit, period, parameters):
 
         # Calculate benefit as payment standard minus countable income
         calculated_benefit = max_(payment_standard - countable_income, 0)
+        capped_benefit = min_(calculated_benefit, payment_standard)
 
         # Apply minimum grant rule
-        return max_(calculated_benefit, p.minimum_grant)
+        return max_(capped_benefit, p.minimum_grant)