Deterministic 1084.No LLM in the Math Path.
7 income types. Fannie Mae 1084-compliant. Reproducible, auditable calculations that match what a senior underwriter produces on a manual worksheet — with automated 2-year trending and variance flagging.
The Critical Differentiator
Most AI-powered LOS platforms route income questions through a language model. LLMs are excellent at language — they are not reliable arithmetic engines. When it's your borrower's income determining their ability to repay a 30-year mortgage, you don't want approximation.
Confer's income calculation engine is explicitly deterministic. The codebase constraint reads: "No LLM calls are permitted in this module." Every income figure is the product of defined arithmetic rules — producing an auditable, reproducible result.
Why Income Calculation Is the #1 Automation Target
ACES Quality Management data shows income and employment defects at 25% of all critical defects for five consecutive quarters — the #1 QC defect category in mortgage origination. Assets rank second at 16.67%.
The root cause is structural: self-employed income requires cross-referencing Schedule C, Schedule E, and K-1 forms, applying specific Fannie Mae 1084 add-back rules, and computing 2-year trending — each step is an opportunity for manual error. Deterministic automation eliminates this entire error class.
7 Income Types, Zero Guesswork
Each income type has a dedicated calculator with agency-specific add-backs and trending logic.
| Income Type | Calculation Method | Guideline | Add-Backs Applied |
|---|---|---|---|
| W-2 Salary / Wages | YTD gross + 2-year W-2 average, cross-checked against pay stub pay frequency and employer continuity | Fannie Mae B3-3.1 | None (base wage income) |
| Self-Employment (Schedule C) | Net profit + depreciation + amortization + business use of home + 50% meals deduction | Fannie Mae 1084, Section 1 | Depreciation, amortization, business-use-of-home, 50% meals |
| Rental Income (Schedule E) | Gross rents minus operating expenses, 75% vacancy factor applied, subject property income/loss treated separately | Fannie Mae B3-3.1-05 | Depreciation, depletion, amortization |
| K-1 (Partnership / S-Corp) | Pass-through income with 1084-compliant add-backs; ownership percentage applied per agency requirements | Fannie Mae 1084, Section 2 / 3 | Depreciation, depletion, amortization, non-recurring losses |
| Investment Income | Dividend and interest income 2-year average (Schedule B), trending analysis for continuance | Fannie Mae B3-3.1-09 | Not applicable |
| Retirement / Pension | Social Security award letter amount, pension/annuity 1099-R gross, continuance verification | Fannie Mae B3-3.1-09 | Not applicable |
| Other Income | Alimony, child support, VA benefits, disability — documented per agency continuance requirements (3 years remaining) | Fannie Mae B3-3.1-09 | Not applicable |
Built-in Automation
2-Year Trending
Automatic year-over-year income trend analysis. Declining income flagged with specific reason code.
Variance Flags
Income variance >10% → 'needs review'. >25% → critical hold. Both include audit documentation.
Multi-Entity Support
Self-employed borrowers with multiple employer entities, complex Sch. C deductions, and K-1 pass-through handled natively.
Document Auto-Extraction
W-2 Box 1 wages, pay stub YTD gross, and 1040 AGI auto-extracted from AI-classified documents.
Cross-Reference Engine
Extracted income figures automatically compared against the application record. Discrepancies surfaced before underwriter review.
Audit Trail
Every calculation step is logged. Full, reproducible audit trail for QC and regulatory examination.
Questions
What does 'deterministic' mean for income calculation?
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Deterministic means the calculation engine uses defined arithmetic rules — not a language model estimation. Every income figure is the product of reproducible, auditable formulas that match what a senior underwriter would produce on a manual 1084 worksheet. No AI guessing is involved in the math path.
How does Confer calculate Schedule C self-employment income?
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The Schedule C calculator applies Fannie Mae-required add-backs: depreciation, amortization, business use of home, and 50% meals deduction. Net profit is combined with add-backs, and a 2-year trending analysis runs automatically. Income declining more than 10% triggers a 'needs review' flag with the specific reason documented.
Does Confer handle K-1 pass-through income?
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Yes. Confer includes dedicated K-1 calculators for partnership and S-Corp income, applying Fannie Mae 1084-compliant add-backs for depreciation, depletion, and amortization from the partnership/S-Corp. Ownership percentage is factored in per agency guidelines.
What triggers an income variance flag?
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Income declining more than 10% year-over-year triggers an automated 'needs review' flag. A decline greater than 25% triggers a critical hold. Both include the specific reason documented for the underwriter's review.
Does the income calculator work with Encompass?
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Yes. Confer syncs income calculation results bidirectionally with Encompass through 180+ field mappings. Calculated income figures, source documentation, and variance flags are mapped to corresponding Encompass fields. Lenders using Encompass as their system of record can run Confer's deterministic income engine and have results reflected in Encompass automatically.
How does Confer's income calculation compare to LLM-based tools?
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LLM-based tools estimate income from document text — they are language models, not arithmetic engines. Confer's engine applies defined mathematical rules with Fannie Mae 1084-compliant add-backs, producing reproducible results that match what a senior underwriter produces manually. The codebase enforces a constraint: 'No LLM calls are permitted in this module.' This matters because income and employment defects account for 25% of all critical QC defects according to ACES data — five consecutive quarters as the #1 defect category.
See the Calculator Live
Bring a Schedule C return. Watch Confer calculate qualified income, apply every add-back, run 2-year trending, and produce a clean audit trail — in seconds.