Northwest Territories Credit

Fixes PolicyEngine#229

policyengine_canada/parameters/gov/provinces/nt/tax/income/credits/living_tax_credit/threshold/middle/base.yaml

@@ -6,4 +6,4 @@ metadata:
   label: Northwest Territories living tax credit high income base
   reference:
   - title: Government of Canada - Credit
-    href: https://www.canada.ca/en/revenue-agency/services/forms-publications/tax-packages-years/general-income-tax-benefit-package/northwest-territories/5012-tc.html 
+    href: https://www.canada.ca/en/revenue-agency/services/forms-publications/tax-packages-years/general-income-tax-benefit-package/northwest-territories/5012-tc.html 

policyengine_canada/parameters/gov/provinces/nt/tax/income/credits/living_tax_credit/threshold/middle/supplement.yaml

@@ -1,6 +1,6 @@
 description: Northwest Territories living tax credit middle income supplement
 values:
-  2022-12-31: 762 
+  2022-12-31: 312
 metadata:
   unit: currency-CAD
   label: Northwest Territories living tax credit middle income supplement

policyengine_canada/tests/gov/provinces/nt/tax/income/credits/living_tax_credit/nt_living_tax_credit.yaml

@@ -2,30 +2,62 @@
   period: 2023
   input:
     province_code: NT
-    nt_income_tax_before_credits: 10_000
+    individual_net_income: 12_000
+  output:
+    nt_living_tax_credit: 312
+
+- name: Income below 12_000
+  period: 2023
+  input:
+    province_code: NT
+    individual_net_income: 10_000
   output:
     nt_living_tax_credit: 260
 
 - name: Income between 12_000 and 48_000
   period: 2023
   input:
     province_code: NT
-    nt_income_tax_before_credits: 42_000
+    individual_net_income: 42_000
   output:
     nt_living_tax_credit: 687
 
+- name: Income between 12_000 and 48_000
+  period: 2023
+  input:
+    province_code: NT
+    individual_net_income: 48_000
+  output:
+    nt_living_tax_credit: 762
+
+- name: Income between 48_000 and 66_000
+  period: 2023
+  input:
+    province_code: NT
+    individual_net_income: 58_000
+  output:
+    nt_living_tax_credit: 862
+
 - name: Income between 48_000 and 66_000
   period: 2023
   input:
     province_code: NT
-    nt_income_tax_before_credits: 58_000
+    individual_net_income: 65_999
   output:
-    nt_living_tax_credit: 772
+    nt_living_tax_credit: 941.99
 
 - name: Income above 66_000 
   period: 2023
   input:
     province_code: NT
-    nt_income_tax_before_credits: 67_000
+    individual_net_income: 67_000
+  output:
+    nt_living_tax_credit: 942
+
+- name: Income above 66_000 
+  period: 2023
+  input:
+    province_code: NT
+    individual_net_income: 66_001
   output:
     nt_living_tax_credit: 942

policyengine_canada/variables/gov/provinces/nt/tax/income/credits/living_tax_credit/nt_living_tax_credit.py

@@ -12,11 +12,11 @@ def formula(person, period, parameters):
         p = parameters(
             period
         ).gov.provinces.nt.tax.income.credits.living_tax_credit
-        net_income = person("individual_net_income", period)
-        lower = p.threshold.middle.base * p.threshold.low_income_rate
-        middle = (p.threshold.high.base - p.threshold.middle.base) * p.threshold.middle.rate + p.threshold.middle.supplement
-        higher = (net_income - p.income_threshold) * p.threshold.high.rate + p.threshold.high.supplement
+        lower = person("nt_ltc_lower_threshold", period)
+        middle = person("nt_ltc_middle_threshold", period)
+        higher = person("nt_ltc_higher_threshold", period)
 
         return (
             min_(lower + middle + higher, p.max_amount)
         )
+

policyengine_canada/variables/gov/provinces/nt/tax/income/credits/living_tax_credit/nt_ltc_higher_threshold.py

@@ -1,20 +1,20 @@
 from policyengine_canada.model_api import *
 
 
-class ntltc_high_base(Variable):
+class nt_ltc_higher_threshold(Variable):
     value_type = float
     entity = Person
     label = "Higher income for living tax credit"
     definition_period = YEAR
     defined_for = ProvinceCode.NT
 
-    def formula(household, period, parameters):
+    def formula(person, period, parameters):
         p = parameters(
             period
         ).gov.provinces.nt.tax.income.credits.living_tax_credit
         net_income = person("individual_net_income", period)
-        eligible = (p.threshold.high.base < net_income) & (net_income < p.income_threshold)
+        eligible = (p.threshold.high.base < net_income )
 
-        return (
-            (net_income - p.threshold.high.base) * p.threshold.high.rate * eligible + p.threshold.high.supplement
+        return eligible * (
+            (net_income - p.threshold.high.base) * p.threshold.high.rate + p.threshold.high.supplement
         )

policyengine_canada/variables/gov/provinces/nt/tax/income/credits/living_tax_credit/nt_ltc_lower_threshold.py

@@ -15,6 +15,6 @@ def formula(person, period, parameters):
         net_income = person("individual_net_income", period)
         eligible = p.threshold.middle.base >= net_income
 
-        return (
-            net_income * p.threshold.low_income_rate * eligible
+        return eligible * (
+            net_income * p.threshold.low_income_rate 
         )

policyengine_canada/variables/gov/provinces/nt/tax/income/credits/living_tax_credit/nt_ltc_middle_threshold.py

@@ -13,8 +13,8 @@ def formula(person, period, parameters):
             period
         ).gov.provinces.nt.tax.income.credits.living_tax_credit
         net_income = person("individual_net_income", period)
-        eligible = (p.threshold.middle.base < net_income) & (p.threshold.high.base >= net_income)
+        eligible = (p.threshold.middle.base < net_income <= p.threshold.high.base)
 
-        return (
-            (net_income - p.threshold.middle.base) * p.threshold.middle.rate * eligible + p.threshold.middle.supplement
+        return  eligible * (
+            (net_income - p.threshold.middle.base) * p.threshold.middle.rate + p.threshold.middle.supplement
         )