PolicyEngine · juaristi22 · Jul 15, 2025 · Jul 15, 2025 · Jul 15, 2025 · Jul 15, 2025
diff --git a/changelog_entry.yaml b/changelog_entry.yaml
@@ -0,0 +1,4 @@
+- bump: minor
+  changes:
+    added:
+    - Renaming variables to lowercase.
diff --git a/policyengine_uk/entities.py b/policyengine_uk/entities.py
@@ -19,7 +19,7 @@
     containing_entities=["state"],
 )
 
-BenUnit = build_entity(
+ben_unit = build_entity(
     key="benunit",
     plural="benunits",
     label="Benefit unit",
@@ -43,4 +43,4 @@
     is_person=True,
 )
 
-entities = [Household, BenUnit, Person]
+entities = [Household, ben_unit, Person]
diff --git a/...cy/baseline/finance/benefit/family/housing_benefit/housing_benefit_applicable_amount.yaml b/...cy/baseline/finance/benefit/family/housing_benefit/housing_benefit_applicable_amount.yaml
@@ -4,13 +4,13 @@
   input:
     people: 
       person1:
-        is_SP_age: false
+        is_sp_age: false
       person2:
-        is_SP_age: false
+        is_sp_age: false
       person3:
-        is_SP_age: false
+        is_sp_age: false
       person4:
-        is_SP_age: false
+        is_sp_age: false
     benunits:
       benunit:
         members: [person1, person2, person3, person4]
@@ -29,13 +29,13 @@
   input:
     people: 
       person1:
-        is_SP_age: false
+        is_sp_age: false
       person2:
-        is_SP_age: false
+        is_sp_age: false
       person3:
-        is_SP_age: false
+        is_sp_age: false
       person4:
-        is_SP_age: false
+        is_sp_age: false
     benunits:
       benunit:
         members: [person1, person2, person3, person4]
@@ -54,13 +54,13 @@
   input:
     people: 
       person1:
-        is_SP_age: false
+        is_sp_age: false
       person2:
-        is_SP_age: false
+        is_sp_age: false
       person3:
-        is_SP_age: false
+        is_sp_age: false
       person4:
-        is_SP_age: false
+        is_sp_age: false
     benunits:
       benunit:
         members: [person1, person2, person3, person4]
@@ -79,13 +79,13 @@
   input:
     people: 
       person1:
-        is_SP_age: false
+        is_sp_age: false
       person2:
-        is_SP_age: false
+        is_sp_age: false
       person3:
-        is_SP_age: false
+        is_sp_age: false
       person4:
-        is_SP_age: false
+        is_sp_age: false
     benunits:
       benunit:
         members: [person1, person2, person3, person4]
@@ -104,13 +104,13 @@
   input:
     people: 
       person1:
-        is_SP_age: false
+        is_sp_age: false
       person2:
-        is_SP_age: false
+        is_sp_age: false
       person3:
-        is_SP_age: false
+        is_sp_age: false
       person4:
-        is_SP_age: false
+        is_sp_age: false
     benunits:
       benunit:
         members: [person1, person2, person3, person4]
@@ -129,13 +129,13 @@
   input:
     people: 
       person1:
-        is_SP_age: false
+        is_sp_age: false
       person2:
-        is_SP_age: false
+        is_sp_age: false
       person3:
-        is_SP_age: false
+        is_sp_age: false
       person4:
-        is_SP_age: false
+        is_sp_age: false
     benunits:
       benunit:
         members: [person1, person2, person3, person4]

diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/tax_credits.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/tax_credits.yaml
@@ -11,14 +11,14 @@
   input:
     age: 14
   output:
-    is_CTC_child_limit_exempt: true
+    is_ctc_child_limit_exempt: true
 - name: CTC two-child limit non-exemption
   period: 2020
   absolute_error_margin: 0
   input:
     age: 0
   output:
-    is_CTC_child_limit_exempt: false
+    is_ctc_child_limit_exempt: false
 - name: CTC children
   period: 2020
   absolute_error_margin: 0
@@ -31,7 +31,7 @@
       child3:
         age: 1
   output:
-    is_child_for_CTC: [true, true, true]
+    is_child_for_ctc: [true, true, true]
 - name: WTC eligibility for worker
   period: 2020
   absolute_error_margin: 0

diff --git a/policyengine_uk/tests/policy/baseline/gov/dwp/pension_credit/is_pension_credit_eligible.yaml b/policyengine_uk/tests/policy/baseline/gov/dwp/pension_credit/is_pension_credit_eligible.yaml
@@ -3,7 +3,7 @@
   input:
     people:
       person:
-        is_SP_age: false
+        is_sp_age: false
   output:
     is_pension_credit_eligible: false
 
@@ -12,9 +12,9 @@
   input:
     people:
       person:
-        is_SP_age: false
+        is_sp_age: false
       spouse:
-        is_SP_age: true
+        is_sp_age: true
     benunits:
       benunit:
         members: [person, spouse]

diff --git a/policyengine_uk/variables/contrib/ubi_center/basic_income/bi_maximum.py b/policyengine_uk/variables/contrib/ubi_center/basic_income/bi_maximum.py
@@ -11,7 +11,7 @@ class bi_maximum(Variable):
     def formula(person, period, parameters):
         bi = parameters(period).gov.contrib.ubi_center.basic_income
         weekly_flat_amount = bi.amount.flat
-        is_senior_for_bi = person("is_SP_age", period)
+        is_senior_for_bi = person("is_sp_age", period)
         age = person("age", period)
         is_child_for_bi = (age < bi.amount.adult_age) * (
             age >= bi.amount.child_min_age

diff --git a/policyengine_uk/variables/gov/dfe/care_to_learn/would_claim_care_to_learn.py b/policyengine_uk/variables/gov/dfe/care_to_learn/would_claim_care_to_learn.py
@@ -3,10 +3,10 @@
 
 class would_claim_care_to_learn(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "would claim Care to Learn"
     documentation = (
-        "Whether this BenUnit would claim Care to Learn if eligible"
+        "Whether this ben_unit would claim Care to Learn if eligible"
     )
     definition_period = YEAR
     default_value = True
diff --git a/...ine_uk/variables/gov/dfe/extended_childcare_entitlement/extended_childcare_entitlement.py b/...ine_uk/variables/gov/dfe/extended_childcare_entitlement/extended_childcare_entitlement.py
@@ -3,7 +3,7 @@
 
 class extended_childcare_entitlement(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "annual extended childcare entitlement expenses"
     definition_period = YEAR
     unit = GBP

diff --git a/...riables/gov/dfe/extended_childcare_entitlement/extended_childcare_entitlement_eligible.py b/...riables/gov/dfe/extended_childcare_entitlement/extended_childcare_entitlement_eligible.py
@@ -3,7 +3,7 @@
 
 class extended_childcare_entitlement_eligible(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "eligibility for extended childcare entitlement"
     definition_period = YEAR
     defined_for = "would_claim_extended_childcare"

diff --git a/...ariables/gov/dfe/extended_childcare_entitlement/maximum_extended_childcare_hours_usage.py b/...ariables/gov/dfe/extended_childcare_entitlement/maximum_extended_childcare_hours_usage.py
@@ -3,7 +3,7 @@
 
 class maximum_extended_childcare_hours_usage(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "maximum extended childcare hours used"
     documentation = "The maximum number of weekly extended childcare hours that this family uses"
     definition_period = YEAR

diff --git a/...ine_uk/variables/gov/dfe/extended_childcare_entitlement/would_claim_extended_childcare.py b/...ine_uk/variables/gov/dfe/extended_childcare_entitlement/would_claim_extended_childcare.py
@@ -3,7 +3,7 @@
 
 class would_claim_extended_childcare(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "would claim extended childcare entitlement"
     documentation = "Whether this family would claim extended childcare entitlement if eligible"
     definition_period = YEAR

diff --git a/...ted_childcare_entitlement/meets_tax_credit_criteria_for_targeted_childcare_entitlement.py b/...ted_childcare_entitlement/meets_tax_credit_criteria_for_targeted_childcare_entitlement.py
@@ -3,7 +3,7 @@
 
 class meets_tax_credit_criteria_for_targeted_childcare_entitlement(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "meets Tax Credit criteria for targeted childcare entitlement"
     definition_period = YEAR
 

diff --git a/...ildcare_entitlement/meets_universal_credit_criteria_for_targeted_childcare_entitlement.py b/...ildcare_entitlement/meets_universal_credit_criteria_for_targeted_childcare_entitlement.py
@@ -5,7 +5,7 @@ class meets_universal_credit_criteria_for_targeted_childcare_entitlement(
     Variable
 ):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = (
         "meets Universal Credit criteria for targeted childcare entitlement"
     )

diff --git a/...riables/gov/dfe/targeted_childcare_entitlement/targeted_childcare_entitlement_eligible.py b/...riables/gov/dfe/targeted_childcare_entitlement/targeted_childcare_entitlement_eligible.py
@@ -3,7 +3,7 @@
 
 class targeted_childcare_entitlement_eligible(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "eligibility for targeted childcare entitlement"
     definition_period = YEAR
     defined_for = "would_claim_targeted_childcare"

diff --git a/...ine_uk/variables/gov/dfe/targeted_childcare_entitlement/would_claim_targeted_childcare.py b/...ine_uk/variables/gov/dfe/targeted_childcare_entitlement/would_claim_targeted_childcare.py
@@ -3,7 +3,7 @@
 
 class would_claim_targeted_childcare(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "would claim targeted childcare entitlement"
     documentation = "Whether this family would claim targeted childcare entitlement if eligible"
     definition_period = YEAR

diff --git a/...e_uk/variables/gov/dfe/universal_childcare_entitlement/would_claim_universal_childcare.py b/...e_uk/variables/gov/dfe/universal_childcare_entitlement/would_claim_universal_childcare.py
@@ -3,8 +3,8 @@
 
 class would_claim_universal_childcare(Variable):
     value_type = bool
-    entity = BenUnit
+    entity = ben_unit
     label = "would claim universal childcare entitlement"
-    documentation = "Whether this BenUnit would claim universal childcare entitlement if eligible"
+    documentation = "Whether this ben_unit would claim universal childcare entitlement if eligible"
     definition_period = YEAR
     default_value = True
diff --git a/policyengine_uk/variables/gov/dwp/BRMA_LHA_rate.py b/policyengine_uk/variables/gov/dwp/BRMA_LHA_rate.py
@@ -12,7 +12,7 @@
 
 class BRMA_LHA_rate(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "LHA rate"
     documentation = "Local Housing Allowance rate"
     definition_period = YEAR

diff --git a/policyengine_uk/variables/gov/dwp/CTC_child_element.py b/policyengine_uk/variables/gov/dwp/CTC_child_element.py
@@ -3,7 +3,7 @@
 
 class CTC_child_element(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "Child Tax Credit child element"
     definition_period = YEAR
     reference = "Tax Credits Act 2002 s. 9"
@@ -12,14 +12,14 @@ class CTC_child_element(Variable):
     def formula(benunit, period, parameters):
         person = benunit.members
         CTC = parameters(period).gov.dwp.tax_credits.child_tax_credit
-        is_child_for_CTC = person("is_child_for_CTC", period)
-        is_CTC_child_limit_exempt = person("is_CTC_child_limit_exempt", period)
-        exempt_child = is_child_for_CTC & is_CTC_child_limit_exempt
+        is_child_for_ctc = person("is_child_for_ctc", period)
+        is_ctc_child_limit_exempt = person("is_ctc_child_limit_exempt", period)
+        exempt_child = is_child_for_ctc & is_ctc_child_limit_exempt
         exempt_children = benunit.sum(exempt_child)
         child_limit = CTC.limit.child_count
         spaces_left = max_(0, child_limit - exempt_children)
         non_exempt_children = min_(
-            spaces_left, benunit.sum(is_child_for_CTC) - exempt_children
+            spaces_left, benunit.sum(is_child_for_ctc) - exempt_children
         )
         children = exempt_children + non_exempt_children
         return CTC.elements.child_element * children
diff --git a/policyengine_uk/variables/gov/dwp/CTC_disabled_child_element.py b/policyengine_uk/variables/gov/dwp/CTC_disabled_child_element.py
@@ -3,17 +3,17 @@
 
 class CTC_disabled_child_element(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "CTC entitlement from disabled child elements"
     definition_period = YEAR
     reference = "Tax Credits Act 2002 s. 9"
     unit = GBP
 
     def formula(benunit, period, parameters):
         person = benunit.members
-        is_child_for_CTC = person("is_child_for_CTC", period)
+        is_child_for_ctc = person("is_child_for_ctc", period)
         is_disabled_for_benefits = person("is_disabled_for_benefits", period)
-        is_disabled_child = is_child_for_CTC & is_disabled_for_benefits
+        is_disabled_child = is_child_for_ctc & is_disabled_for_benefits
         disabled_children = benunit.sum(is_disabled_child)
         CTC = parameters(period).gov.dwp.tax_credits.child_tax_credit
         amount = CTC.elements.dis_child_element * disabled_children

diff --git a/policyengine_uk/variables/gov/dwp/CTC_family_element.py b/policyengine_uk/variables/gov/dwp/CTC_family_element.py
@@ -3,7 +3,7 @@
 
 class CTC_family_element(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "CTC entitlement in the Family Element"
     definition_period = YEAR
     reference = "Tax Credits Act 2002 s. 9"

diff --git a/policyengine_uk/variables/gov/dwp/CTC_maximum_rate.py b/policyengine_uk/variables/gov/dwp/CTC_maximum_rate.py
@@ -3,7 +3,7 @@
 
 class CTC_maximum_rate(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "Maximum Child Tax Credit"
     definition_period = YEAR
     reference = "Tax Credits Act 2002 s. 9"

diff --git a/policyengine_uk/variables/gov/dwp/CTC_severely_disabled_child_element.py b/policyengine_uk/variables/gov/dwp/CTC_severely_disabled_child_element.py
@@ -3,7 +3,7 @@
 
 class CTC_severely_disabled_child_element(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "CTC entitlement from severely disabled child elements"
     definition_period = YEAR
     reference = "Tax Credits Act 2002 s. 9"
@@ -12,12 +12,12 @@ class CTC_severely_disabled_child_element(Variable):
 
     def formula(benunit, period, parameters):
         person = benunit.members
-        is_child_for_CTC = person("is_child_for_CTC", period)
+        is_child_for_ctc = person("is_child_for_ctc", period)
         is_severely_disabled_for_benefits = person(
             "is_severely_disabled_for_benefits", period
         )
         is_severely_disabled_child = (
-            is_child_for_CTC & is_severely_disabled_for_benefits
+            is_child_for_ctc & is_severely_disabled_for_benefits
         )
         severely_disabled_children = benunit.sum(is_severely_disabled_child)
         CTC = parameters(period).gov.dwp.tax_credits.child_tax_credit

diff --git a/policyengine_uk/variables/gov/dwp/LHA_allowed_bedrooms.py b/policyengine_uk/variables/gov/dwp/LHA_allowed_bedrooms.py
@@ -8,7 +8,7 @@
 
 class LHA_allowed_bedrooms(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "The number of bedrooms covered by LHA for the benefit unit"
     definition_period = YEAR
     reference = "https://www.legislation.gov.uk/uksi/2013/376/schedule/4/paragraph/10/2021-04-06"

diff --git a/policyengine_uk/variables/gov/dwp/LHA_cap.py b/policyengine_uk/variables/gov/dwp/LHA_cap.py
@@ -8,7 +8,7 @@
 
 class LHA_cap(Variable):
     value_type = float
-    entity = BenUnit
+    entity = ben_unit
     label = "Applicable amount for LHA"
     documentation = "Applicable amount for Local Housing Allowance"
     definition_period = YEAR