Merge pull request #1381 from MaxGhenis/MaxGhenis/issue1004

Add FPG-based basic income element

changelog_entry.yaml

@@ -0,0 +1,6 @@
+- bump: minor
+  changes:
+    added:
+      - Federal poverty guideline-based basic income element.
+    changed:
+      - Made all basic income variables tax unit-level.

openfisca_us/parameters/contrib/ubi_center/basic_income/fpg_percent.yaml

@@ -0,0 +1,7 @@
+description: A basic income is provided to tax units at this percentage of the federal poverty guideline
+values:
+  0000-01-01: 0
+metadata:
+  unit: /1
+  name: bi_fpg_percent
+  label: Basic income as a percent of tax unit's poverty line

openfisca_us/tests/policy/baseline/contrib/ubi_center/basic_income.yaml

@@ -1,15 +1,8 @@
 - name: Basic income with phase-out applied.
   period: 2022
-  absolute_error_margin: 1
   input:
-    people:
-      adult:
-        basic_income_before_phase_out: 10_000
-      child:
-        basic_income_before_phase_out: 5_000
-    tax_units:
-      tax_unit:
-        members: [adult, child]
-        basic_income_phase_out: 5_000
+    basic_income_before_phase_out: 10_000
+    basic_income_phase_out: 4_000
+    basic_income_eligible: true
   output:
-    basic_income: [6_667, 3_333]
+    basic_income: 6_000

openfisca_us/tests/policy/baseline/contrib/ubi_center/basic_income_before_phase_out.yaml

@@ -12,4 +12,12 @@
       tax_unit:
         members: [adult, child]
   output:
-    basic_income_before_phase_out: [10_000, 5_000]
+    basic_income_before_phase_out: 15_000
+
+- name: 100% of FPG.
+  period: 2022
+  input:
+    contrib.ubi_center.basic_income.fpg_percent: 1
+    tax_unit_fpg: 10_000
+  output:
+    basic_income_before_phase_out: 10_000

openfisca_us/variables/contrib/ubi_center/basic_income/basic_income.py

@@ -3,21 +3,14 @@
 
 class basic_income(Variable):
     value_type = float
-    entity = Person
+    entity = TaxUnit
     label = "Basic income"
     unit = USD
-    documentation = "Total basic income payments for this person. Phase-outs as an equal percentage to all tax unit members."
+    documentation = "Total basic income payments for this filer."
     definition_period = YEAR
 
-    def formula(person, period, parameters):
-        eligible = person.tax_unit("basic_income_eligible", period)
-        basic_income = person("basic_income_before_phase_out", period)
-        tax_unit = person.tax_unit
-        tax_unit_basic_income = tax_unit.sum(basic_income)
-        tax_unit_phase_out = tax_unit("basic_income_phase_out", period)
-        percent_reduction = where(
-            tax_unit_basic_income > 0,
-            tax_unit_phase_out / tax_unit_basic_income,
-            0,
-        )
-        return basic_income * eligible * (1 - percent_reduction)
+    def formula(tax_unit, period, parameters):
+        eligible = tax_unit("basic_income_eligible", period)
+        basic_income = tax_unit("basic_income_before_phase_out", period)
+        phase_out = tax_unit("basic_income_phase_out", period)
+        return eligible * (basic_income - phase_out)

openfisca_us/variables/contrib/ubi_center/basic_income/basic_income_before_phase_out.py

@@ -3,15 +3,19 @@
 
 class basic_income_before_phase_out(Variable):
     value_type = float
-    entity = Person
+    entity = TaxUnit
     label = "Basic income before phase-outs"
     unit = USD
-    documentation = (
-        "Total basic income payments for this person, before phasing out."
-    )
     definition_period = YEAR
 
-    def formula(person, period, parameters):
+    def formula(tax_unit, period, parameters):
         p = parameters(period).contrib.ubi_center.basic_income
+        # Start with person-level amount.
+        person = tax_unit.members
         age = person("age", period)
-        return p.amount_by_age.calc(age)
+        amount = p.amount_by_age.calc(age)
+        person_level_amount = tax_unit.sum(amount)
+        # Now compute FPG amount.
+        fpg = tax_unit("tax_unit_fpg", period)
+        fpg_amount = p.fpg_percent * fpg
+        return person_level_amount + fpg_amount