Match capped value of non-refundable federal credits in state credits

changelog_entry.yaml

@@ -0,0 +1,6 @@
+- bump: patch
+  changes:
+    fixes:
+    - Accurately reflect non-refundable state credit matches if federal credit amounts exceed taxes.
+    - Maine child care credit calculation.
+    - Kansas CDCC calculation.

policyengine_us/parameters/gov/territories/pr/tax/income/gross_income/sources.yaml

@@ -41,4 +41,4 @@ metadata:
     - title: P.R. Laws tit. 13, § 30101 
       href: https://law.justia.com/codes/puerto-rico/title-thirteen/subtitle-17/part-ii/chapter-1005/subchapter-a/30101/
     - title: P.R. Individual Income Tax Return, Form 482
-      href: https://hacienda.pr.gov/sites/default/files/individuals_2024_rev._jul_12_24_9-30-24_informative.pdf#page=2
+      href: https://hacienda.pr.gov/sites/default/files/individuals_2024_rev._jul_12_24_9-30-24_informative.pdf#page=2

policyengine_us/tests/policy/baseline/gov/states/ks/tax/income/ks_cdcc.yaml

@@ -3,5 +3,44 @@
   input:
     cdcc: 1_000
     state_code: KS
+    income_tax_before_credits: 2_000
   output:
     ks_cdcc: 0.25 * 1_000
+
+- name: Taxsim integration test
+  absolute_error_margin: 2
+  period: 2023
+  input:
+    people:
+      person1:
+        age: 40
+        employment_income: 20000
+        ssi: 0
+        wic: 0
+        deductible_mortgage_interest: 0
+      person2:
+        age: 4
+        employment_income: 0
+        ssi: 0
+        wic: 0
+        deductible_mortgage_interest: 0
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+        tax_unit_childcare_expenses: 2_000
+        premium_tax_credit: 0
+        local_income_tax: 0
+        state_sales_tax: 0
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+        snap: 0
+        tanf: 0
+    households:
+      household:
+        members: [person1, person2]
+        state_fips: 20
+  output:
+    income_tax_before_credits: 0
+    ks_cdcc: 0
+    ks_income_tax: -455

policyengine_us/tests/policy/baseline/gov/states/me/tax/income/credits/child_care_credit.yaml → policyengine_us/tests/policy/baseline/gov/states/me/tax/income/credits/me_child_care_credit.yaml

@@ -57,3 +57,40 @@
     me_child_care_credit: 750
     me_refundable_child_care_credit: 500
     me_non_refundable_child_care_credit: 250
+
+- name: Taxsim integration test
+  absolute_error_margin: 2
+  period: 2023
+  input:
+    people:
+      person1:
+        age: 40
+        employment_income: 20_002
+        ssi: 0
+        wic: 0
+        deductible_mortgage_interest: 0
+      person2:
+        age: 4
+        employment_income: 1
+        ssi: 0
+        wic: 0
+        deductible_mortgage_interest: 0
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+        tax_unit_childcare_expenses: 0
+        premium_tax_credit: 0
+        local_income_tax: 0
+        state_sales_tax: 0
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+        snap: 0
+        tanf: 0
+    households:
+      household:
+        members: [person1, person2]
+        state_fips: 23
+  output:
+    me_child_care_credit: 0
+    me_income_tax: -1_199

policyengine_us/variables/gov/states/ks/tax/income/credits/ks_cdcc.py

@@ -15,4 +15,12 @@ class ks_cdcc(Variable):
 
     def formula(tax_unit, period, parameters):
         p = parameters(period).gov.states.ks.tax.income.credits
-        return p.cdcc_fraction * tax_unit("cdcc", period)
+        # The credit match is limited to the amount of CDCC claimed
+        # we will represent this by capping the CDCC at federal income tax
+        # before non-refundable credits
+        cdcc = tax_unit("cdcc", period)
+        income_tax_before_credits = tax_unit(
+            "income_tax_before_credits", period
+        )
+        capped_cdcc = min_(cdcc, income_tax_before_credits)
+        return p.cdcc_fraction * capped_cdcc

policyengine_us/variables/gov/states/me/tax/income/credits/child_care_credit/me_child_care_credit.py

@@ -22,10 +22,14 @@ def formula(tax_unit, period, parameters):
         )
         # Line 2: Divide Federal CDCC according to share of regular vs. Step 4 expenses
         cdcc = tax_unit("cdcc", period)
+        income_tax_before_credits = tax_unit(
+            "income_tax_before_credits", period
+        )
+        capped_cdcc = min_(cdcc, income_tax_before_credits)
         # Line 2a: Column A
-        cdcc_regular_portion = cdcc * (1 - step_4_share_of_expenses)
+        cdcc_regular_portion = capped_cdcc * (1 - step_4_share_of_expenses)
         # Line 2a, Column B
-        cdcc_step_4_portion = cdcc * step_4_share_of_expenses
+        cdcc_step_4_portion = capped_cdcc * step_4_share_of_expenses
         # Line 3, Column A
         regular_child_care_credit = (
             p.share_of_federal_credit.non_step_4 * cdcc_regular_portion