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DFAST 2026 Severely Adverse Scenario

Default Sequencing Stress Test

How do consumers prioritise debt payments when the economy collapses? 476 digital twins reveal the payment hierarchy, tipping points, and generational fault lines that macro models miss.
476
Digital Twins
13
Questions
10%
Peak Unemployment
90%
Protect Mortgage

The Scenario

Fed’s Proposed 2026 Severely Adverse Scenario

The Federal Reserve’s most extreme stress test scenario, translated into consumer-level questions.

The Shock: A deep recession hits. Unemployment doubles from 4.5% to 10%. House prices crash 29%. The stock market drops 54%. Commercial real estate falls 40%. The Fed slashes rates to near zero. BBB corporate spreads blow out to 5.7 percentage points. This is 2008 again — maybe worse.

The Method: 476 digital twins — synthetic consumer personas representing a cross-section of US borrowers — were asked 13 questions across four domains: payment priority, default tipping points, negative equity behaviour, and post-crisis recovery. Each twin responded based on their individual financial profile, attitudes, and circumstances.

The Purpose: To provide the behavioural layer underneath a bank’s DFAST loss model. Macro regressions tell you how much defaults rise. Twins tell you who defaults, when, and in what order.

Unemployment
10%
from 4.5%
House Prices
↓29%
to trough Q4 2027
Equities
↓54%
through Q3 2026
CRE Prices
↓40%
to trough Q4 2027
3m Treasury
0.1%
from 4.0%

Panel Composition

Gen Z
35
7% of panel
Millennials
170
36% of panel
Gen X
173
36% of panel
Boomers
92
19% of panel

Financial Profile of Panel

No Savings (<3 months)
54%
258 twins
Previously Unemployed 3mo+
43%
203 twins
No Debt At All
32%
152 twins
Has Mortgage
20%
90 twins

Part 1

The Payment Hierarchy

When money runs out, what gets cut first — and what gets protected at all costs?

Which bill do you cut first after a job loss?

BNPL
49%
Credit card
48%
Car loan
1.5%
Insurance
1.1%
Personal loan
Utilities

Which bill do you protect at all costs?

Mortgage / rent
90%
Utilities
6.7%
Car loan
3.2%
Credit card

Generational Split: What Gets Cut First

Gen Z
71%
cut BNPL first
Millennials
~50/50
BNPL & credit card
Gen X
53%
cut credit card first
Boomers
57%
cut credit card first
Key Finding

BNPL is the canary in the coal mine for Gen Z. 71% of Gen Z twins cut BNPL first, vs. 41% of Boomers. For a bank monitoring early-warning signals of consumer stress, BNPL delinquency in the under-35 segment is the leading indicator — it will show up before credit cards, well before mortgages.

How This Compares to Real-World Data

Brox Twin Data (2026)
Payment priority: Mortgage > utilities > car > credit card/BNPL. Housing is sacred (90% protect it at all costs).
First to cut: BNPL (49%) and credit cards (48%) are nearly tied overall, but split sharply by generation.
Car loans: Only 1.5% would cut car payments first. Cars are highly protected.
TransUnion Actual Data (2008–2012)
Payment priority: Auto > credit card > mortgage. During the 2008 crisis, consumers paid car loans first, credit cards second, mortgages last.
2009 delinquency rates: Auto 1.34%, credit cards 2.82%, mortgages 3.83% — confirming the hierarchy.
Key difference: BNPL did not exist in 2008. Twin data suggests it now sits below credit cards in the payment hierarchy — the new lowest-priority debt.
Validation

Twin data aligns with the TransUnion payment hierarchy. Cars are protected, unsecured debt gets cut. The twins add a layer TransUnion’s historical data cannot: BNPL as a new, lowest-priority debt class that will show stress signals first in the next downturn, particularly among younger borrowers. LendingTree reports 41% of BNPL users already made late payments in the past year — before any recession.


Part 2

Mortgage Default Tipping Points

When does a missed mortgage payment actually happen? For most borrowers, the answer is: much later than macro models assume.
Hold Out as Long as Possible
65%
Cut everything else first
Sell or Move First
21%
Before missing a payment
Default in 1–2 Months
10%
After losing income
Miss Immediately
2%
No buffer at all

When would you miss a mortgage payment?

Cut all other spending first, hold out
65%
Sell or move before missing
21%
After 1–2 months of no income
10%
Miss it almost immediately
2.1%
After 3–6 months
1.5%

If a family member lends you money, where does it go?

Living expenses (food, bills)
69%
Mortgage
29%
Car
1.5%
Credit card

Gen Z vs. Boomers: Where Family Money Goes

Gen Z (n=35)
94% use family money for living expenses
3% direct it to mortgage
They’re covering food and bills, not servicing debt. Most don’t have mortgages.
Boomers (n=92)
55% use family money for living expenses
43% direct it to mortgage
Nearly half prioritise the house. Protecting the home is deeply ingrained.
Implication for Loss Models

86% of twins would either exhaust all other options or sell before missing a mortgage payment. Only 12% crack within the first two months of income loss. This suggests mortgage default rates in the early months of a recession may be lower than macro models predict — but when they do come, they come in a concentrated wave from the most vulnerable segments.


Part 3

Negative Equity: The Generational Fault Line

When your home is worth 30% less than what you owe, do you keep paying? The answer depends almost entirely on how old you are.
Keep Paying Regardless
59%
Overall
Try to Sell or Negotiate
37%
Overall
Stop Paying (Strategic Default)
3.6%
Overall

Response to 30% Negative Equity — By Generation

GenerationKeep PayingSell / NegotiateStop Paying
Gen Z29%60%11%
Gen X61%35%4%
Boomers79%20%1%
Gen Z Strategic Default
11%
would stop paying
Gen X Strategic Default
4%
would stop paying
Boomer Strategic Default
1%
would stop paying
Critical Risk

Gen Z is 11× more likely to strategically default than Boomers. At 30% negative equity, 11% of Gen Z twins would stop paying outright and 60% would try to exit. A macro model that applies a single strategic default rate across the mortgage book is materially wrong. Loss-given-default models need a generational overlay.

How This Compares to Real-World Data

Brox Twin Data (2026)
3.6% overall would strategically default at 30% negative equity.
Gen Z: 11% would stop paying. Boomers: 1%.
59% would keep paying regardless of home value decline.
Federal Reserve Research (2010–2020)
~4% actual strategic default rate among borrowers who could have defaulted (Fed study of 2008 crisis data).
17% said they would default at -50% equity (survey). Median borrower doesn’t default until -62%.
~90% of Americans said it is not OK to stop paying even if underwater (Fannie Mae 2010 survey).
Validation

Twin overall strategic default rate (3.6%) closely matches the Fed’s observed rate (~4%) from the 2008 crisis. The moral aversion to strategic default is real and shows in the data. But the generational breakdown is new — Gen Z at 11% is materially higher than any historically observed rate, and there is no 2008-era data on this cohort. This is a forward-looking risk that historical regressions cannot capture.


Part 4

Recovery Behaviour & Bank Loyalty

What happens after the crisis ends? Who stays, who leaves, and what drives the decision?

Post-crisis: What’s your first financial priority?

Catch up on mortgage
68%
Pay off credit card
24%
Rebuild savings
7.8%

Gen Z Recovery Priorities vs. Boomers

Gen Z (n=35)
49% catch up on mortgage
34% pay off credit card
17% rebuild savings
More balanced — savings and credit card compete with mortgage.
Boomers (n=92)
72% catch up on mortgage
26% pay off credit card
2% rebuild savings
Single-minded — protect the house, then deal with unsecured debt.

After the crisis, do you stay with your bank?

Depends How They Treated Me
93%
Conditional loyalty
Stay Regardless
6%
Unconditional
Shop Around
1%
Definite leavers
Retention Finding

93% of twins say bank loyalty depends entirely on crisis-period treatment. This matches industry data: 62% of bank customers say they would switch if treated impersonally, and responsive support is a top-3 retention driver. The implication is clear — investment in forbearance programmes, responsive customer service, and proactive outreach during a downturn directly determines post-crisis churn. Banks that go dark during the recession will lose customers on the other side.


Part 5

Bankruptcy Is Not on the Table

The nuclear option is almost universally rejected — until there is absolutely no alternative.
Only as Absolute Last Resort
99%
470 of 476 twins
Never
1%
5 twins
When I Miss 3+ Payments
0.2%
1 twin
Implication

Consumers will exhaust every other option before considering bankruptcy or formal debt management. This means the payment hierarchy — BNPL → credit cards → personal loans → car → mortgage → utilities — will play out in full before formal insolvency enters the picture. Loss models should expect a long tail of delinquency before charge-offs in any segment.


Key Findings

What the Twins Tell a Bank Risk Team

Six findings that macro regression models cannot produce.
Finding 1 — BNPL Is the Canary

BNPL gets cut first by 49% of twins, rising to 71% among Gen Z. This is a new debt class that did not exist in 2008, so historical regressions cannot model its behaviour. Real-world data already confirms the risk: LendingTree reports 41% of BNPL users made late payments in the past year, up from 34%. Gen Z holds 64% BNPL usage with 71% carrying multiple simultaneous loans. In the next downturn, BNPL delinquency in the under-35 segment is the earliest stress signal available.

Finding 2 — Negative Equity Behaviour Is Generational

Overall strategic default at 30% negative equity is 3.6%, closely matching the Fed’s observed ~4% rate from the 2008 crisis. But Gen Z is 11× more likely to walk away than Boomers (11% vs. 1%). A loss model applying a single strategic default rate across the mortgage book will understate risk in young-borrower segments and overstate it in older segments. This generational divergence has no historical precedent to calibrate against.

Finding 3 — The Payment Hierarchy Has a New Bottom Rung

TransUnion’s established hierarchy from 2008 was: auto > credit cards > mortgages. Twin data confirms the structure but adds BNPL below credit cards. The full hierarchy in 2026 is: mortgage/rent > utilities > car > personal loan > credit card > BNPL. During the 2008 recession, consumers prioritised credit cards over mortgages when homes went underwater — that pattern persists, but BNPL now absorbs the first wave of stress.

Finding 4 — Mortgage Resilience Is Higher Than Expected

86% of twins would either exhaust all other options or sell before missing a mortgage payment. Only 12% default within the first two months of income loss. This suggests the early-stage mortgage delinquency rate in a recession may be lower than a linear macro model assumes — with losses concentrated later and in specific vulnerable segments rather than spread evenly.

Finding 5 — Bank Loyalty Is Earned During the Crisis

93% of twins say post-crisis bank loyalty depends on how they were treated during the downturn. Only 6% would stay unconditionally, and only 1% would definitely leave. Industry data corroborates this: 62% of customers will switch if treated impersonally. Banks that invest in forbearance and responsive service during the recession retain customers. Banks that don’t face a churn wave on recovery.

Finding 6 — Bankruptcy Is the Last Resort, Not a Strategy

99% say bankruptcy or debt management is only considered as an absolute last resort. No segment shows proactive consideration of formal insolvency. The full payment hierarchy will play out — from BNPL to credit cards to personal loans to secured debt — before charge-offs or formal defaults materialise. This implies a long delinquency-to-default runway that can be used for early intervention.