Add Nebraska TANF Program

[hua7450]

Summary

Closes #7040

Implements Nebraska Aid to Dependent Children (ADC), the state's TANF program.

Regulatory Authority

Primary Legal Sources

1. Nebraska Revised Statutes

   • Section 43-504: Definition of dependent child (age requirements)
   • Section 43-512: ADC application, payment level (55% of Standard of Need), minimum payment ($10)
   • Section 43-513: Standard of Need, CPI adjustment methodology
   • Section 68-1713: Gap budgeting methodology
   • Section 68-1726: Earned income disregard (50%), resource limits

2. Nebraska Administrative Code Title 468

   • Title 468 Overview: ADC program regulations

Income Eligibility Tests

Standard of Need Test

Countable income (net earned + unearned) must be strictly less than the Standard of Need for the unit size.

Earned Income Disregard: 50% of gross earned income is disregarded for recipients.

• Source: Neb. Rev. Stat. 68-1726(3)(a)(ii)

Income Standards

Unit Size	Need Standard	Payment Standard (55%)
1	$601	$331
2	$741	$408
3	$881	$485
4	$1,021	$562
5	$1,161	$639
6	$1,301	$716
7	$1,441	$793
8	$1,581	$870
9	$1,721	$947
10	$1,861	$1,024
Each additional	+$140	+$77

Formula: Base (1 person) = $601; each additional person = +$140
Source: Neb. Rev. Stat. 43-513

Resource Limits

Unit Size	Resource Limit
1 person	$4,000
2+ persons	$6,000

Source: Neb. Rev. Stat. 68-1726

Benefit Calculation

Gap Budgeting Formula

Nebraska uses "Budget the Gap" methodology:

1. Calculate Net Earned Income: Gross Earned Income * (1 - 0.50)
2. Calculate Gap: Need Standard - Net Earned Income
3. Determine Benefit Before Unearned: min(Gap, Payment Standard)
4. Subtract Unearned Income: Benefit - Unearned Income
5. Apply Minimum Payment Rule: If benefit > $0 but < $10, return $10

Source: Neb. Rev. Stat. 68-1713(1)(p)

Minimum Payment Rule

No ADC payment shall be less than $10 per month.
Source: Neb. Rev. Stat. 43-512

Example Calculation

Family of 3 with $1,000/month gross earned income:

1. Need Standard (size 3): $881
2. Net Earned Income: $1,000 * 0.50 = $500
3. Gap: $881 - $500 = $381
4. Payment Standard: $881 * 0.55 = $485
5. Benefit: min($381, $485) = $381
6. Final (no unearned): $381

Files Added

Parameters (5 files)

policyengine_us/parameters/gov/states/ne/dhhs/adc/
├── need_standard.yaml           # Standard of need by unit size
├── payment_standard_rate.yaml   # 55% of need standard
├── min_payment.yaml             # $10 minimum
├── resource_limit.yaml          # $4,000/$6,000 limits
└── income/
    └── earned_income_disregard.yaml  # 50% disregard

Variables (8 files)

policyengine_us/variables/gov/states/ne/dhhs/adc/
├── ne_adc.py                        # Final benefit amount
├── ne_adc_eligible.py               # Overall eligibility
├── ne_adc_income_eligible.py        # Income test
├── ne_adc_resources_eligible.py     # Resource test
├── ne_adc_countable_earned_income.py # After 50% disregard
├── ne_adc_need_standard.py          # Need standard lookup
├── ne_adc_payment_standard.py       # 55% of need standard
└── ne_adc_maximum_benefit.py        # Gap budgeting result

Tests (7 files, 55 test cases)

policyengine_us/tests/policy/baseline/gov/states/ne/dhhs/adc/
├── integration.yaml                 # 7 end-to-end scenarios
├── ne_adc.yaml                      # 6 benefit tests
├── edge_cases.yaml                  # 24 boundary tests
├── ne_adc_eligible.yaml             # 5 eligibility tests
├── ne_adc_need_standard.yaml        # 5 need standard tests
├── ne_adc_payment_standard.yaml     # 4 payment standard tests
└── ne_adc_countable_earned_income.yaml # 4 disregard tests

Test Coverage

Test Category	Count	Description
Integration tests	7	Full calculation pipeline
Benefit calculations	6	Various income scenarios
Edge cases	24	Boundary conditions, limits
Eligibility	5	Income threshold tests
Need standard	5	Lookup by unit size
Payment standard	4	55% calculation with rounding
Countable income	4	50% disregard application
Total	55

Implementation Notes

1. Simplified Implementation: Uses 50% earned income disregard (recipient rate) for all cases. Nebraska distinguishes between applicants (20%) and recipients (50%), but this requires tracking status that PolicyEngine cannot model.

2. Non-Simulatable Rules: Time limits (60-month lifetime limit), work requirements, and transitional benefits cannot be enforced due to PolicyEngine's single-period architecture.

3. Rounding: Payment standard uses ceiling (np.ceil) to round up to whole dollars.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (9739e2f) to head (a02398a).
⚠️ Report is 17 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##             main     #7041       +/-   ##
============================================
+ Coverage   76.92%   100.00%   +23.07%     
============================================
  Files           1         9        +8     
  Lines          39       121       +82     
  Branches        4         0        -4     
============================================
+ Hits           30       121       +91     
+ Misses          8         0        -8     
+ Partials        1         0        -1     

Flag	Coverage Δ
unittests	100.00% <100.00%> (+23.07%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.