Implement Wisconsin Works (W-2)

[hua7450]

Summary

Implements Wisconsin Works (W-2), Wisconsin's TANF program, with placement-based benefit calculation and automatic placement detection for eligible categories.

Closes #6856
Related: #6869 (prorated CSJ not modeled)

Status

• Parameters created (6 files)
• Variables implemented (7 files)
• Tests written (40 test cases across 7 files)
• CI passing
• Formula verified against Wisconsin Statutes and W-2 Manual
• Ready for review

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Key Changes

Implementation Summary

• ✅ 7 new variables for Wisconsin Works benefit calculation
• ✅ 6 parameter files for placement amounts, income limits, and asset rules
• ✅ 40 comprehensive test cases across 7 test files
• ✅ Placement-based benefits with enum (CSJ, CMC, ARP, W2_TRANSITION)
• ✅ All tests passing

Formula (Per Wisconsin Statutes §§ 49.141-49.161)

Income Eligibility: 115% of Federal Poverty Level

countable_income <= FPL × 1.15

Resource Eligibility: $2,500 limit with $10,000 vehicle exclusion

countable_resources = cash_assets + max(vehicle_value - $10,000, 0)

Benefit Calculation: Placement-based flat payments

benefit = placement_amount[placement_type]

Placement Types:

Placement	Monthly Benefit	Description
CSJ	$653	Community Service Jobs (default)
CMC	$673	Custodial Parent of Infant
ARP	$673	At Risk Pregnancy
W2_TRANSITION	$628	W-2 Transition

Automatic Placement Detection

• CMC: Triggered when household has infant ≤ 2 months
• ARP: Triggered when participant is in 3rd trimester (month 7+)
• CSJ: Default placement for all other eligible households
• W2_TRANSITION: Requires agency assessment (not auto-detected)

---

Files Added

Parameters (6 files)

policyengine_us/parameters/gov/states/wi/dcf/works/
├── asset/
│   ├── limit.yaml                          # $2,500
│   └── vehicle_exclusion.yaml              # $10,000
├── income_limit/
│   └── rate.yaml                           # 1.15 (115% FPL)
└── placement/
    ├── amount.yaml                         # Benefit by placement type
    ├── arp_pregnancy_month_threshold.yaml  # 7 (3rd trimester)
    └── cmc_infant_age_limit.yaml           # 2 months

Variables (7 files)

policyengine_us/variables/gov/states/wi/dcf/works/
├── eligibility/
│   ├── wi_works_eligible.py                # Overall eligibility
│   ├── wi_works_income_eligible.py         # 115% FPL test
│   └── wi_works_resources_eligible.py      # $2,500 asset test
├── income/
│   └── wi_works_countable_income.py        # Earned + unearned - child support
├── resources/
│   └── wi_works_countable_resources.py     # Cash + vehicle (with exclusion)
├── wi_works_placement.py                   # Placement type with auto-detection
└── wi_works.py                             # Main benefit calculation

Tests (7 files, 40 test cases)

policyengine_us/tests/policy/baseline/gov/states/wi/dcf/works/
├── wi_works.yaml                           # 6 tests
├── wi_works_countable_income.yaml          # 5 tests
├── wi_works_countable_resources.yaml       # 6 tests
├── wi_works_eligible.yaml                  # 6 tests
├── wi_works_income_eligible.yaml           # 5 tests
├── wi_works_placement.yaml                 # 7 tests
└── wi_works_resources_eligible.yaml        # 5 tests

---

Example Calculations

Example 1: Family Eligible for CSJ

Household: Single parent with 1 child, no special conditions
Income: $1,000/month earned

FPL for family of 2: ~$21,000/year = $1,750/month
Income limit: $1,750 × 1.15 = $2,013/month
$1,000 < $2,013 → Income eligible ✓

Placement: CSJ (default - no infant, not pregnant)
Benefit: $653/month

Example 2: CMC Placement with Infant

Household: Parent with newborn (1 month old)

Infant age: 1 month ≤ 2 months → CMC eligible
Placement: CMC (Custodial Parent of Infant)
Benefit: $673/month

Example 3: ARP Placement for Third Trimester

Household: Pregnant person in 8th month

Pregnancy month: 8 ≥ 7 → In third trimester
Placement: ARP (At Risk Pregnancy)
Benefit: $673/month

---

Implementation Highlights

Key Features

• ✅ Placement-based benefit calculation with enum
• ✅ Automatic CMC detection (infant ≤ 2 months)
• ✅ Automatic ARP detection (3rd trimester)
• ✅ 115% FPL income test (uses rate, not hardcoded values)
• ✅ $2,500 resource limit with $10,000 vehicle exclusion
• ✅ Child support disregard
• ✅ Citizenship check using federal variable

Design Decisions

1. Placement Enum: Uses WIWorksPlacement enum for type-safe placement handling

   • Enables parameter lookup by placement type
   • Allows future expansion for prorated CSJ

2. FPL Rate Pattern: Uses 1.15 multiplier instead of hardcoded dollar amounts

   • Automatically updates with FPL changes
   • Cleaner and more maintainable

3. Federal Rule Reuse: Uses federal TANF variables

   • is_demographic_tanf_eligible
   • is_citizen_or_legal_immigrant
   • tanf_gross_earned_income
   • tanf_gross_unearned_income

4. Child Support Disregard: Uses adds/subtracts attributes

   • Child support is included in unearned income but fully disregarded
   • Clean and self-documenting

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Known Limitations & Future Enhancements

Not Yet Implemented

1. Prorated CSJ (Wisconsin Works: Add prorated CSJ payment tiers #6869) - Requires modeling hours worked which varies
2. W2_TRANSITION auto-detection - Requires agency assessment
3. Time limits - 24-month/60-month limits require time-series tracking
4. Sanctions - Benefit reductions for non-compliance
5. Lump sum diversion - One-time payments

Simplified Assumptions

• All eligible households receive full placement amount (no proration)
• W2_TRANSITION requires manual assignment
• Uses federal demographic eligibility rules

---

Testing & Verification

Test Results

✅ All 40 tests passing across 7 test files
   - 7 placement tests (CMC, ARP, CSJ scenarios)
   - 33 unit tests (income, resources, eligibility)
   - 0 failures

How to Run

# All tests
policyengine-core test policyengine_us/tests/policy/baseline/gov/states/wi/dcf/works/ -c policyengine_us

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References

Official Sources

• Wisconsin Statutes §§ 49.141-49.161 - W-2 Program
• W-2 Manual 7.4.1 - CSJ Placement
• W-2 Manual 7.4.5 - CMC Placement
• W-2 Manual 7.4.6 - ARP Placement
• W-2 Manual 7.1 - Benefit Amounts

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Branch Information

Branch: integration/wi-tanf-20251123
Base: master
Status: ✅ All tests passing, ready for review

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Implementation by: @hua7450
Issue: #6856
Ready for: Code review and testing feedback

🤖 Generated with Claude Code

Co-Authored-By: Claude [email protected]

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (0ecb2c6) to head (f17bd87).
⚠️ Report is 10 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##            master     #6857   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         7    +5     
  Lines           39       108   +69     
=========================================
+ Hits            39       108   +69     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

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