What if the EU slaps a permanent windfall tax on banks?
A permanent EU windfall levy on bank net-interest income is a European-bank-equity trade: it caps the NII tailwind, slashes dividend/buyback capacity, and reprices Unicredit, Intesa, BNP and the SX7E. Direct analogue is Italy's Aug-2023 surprise bank windfall tax (Italian banks -8% intraday before the cap was softened) and Spain's 2022 levy. The connected angle: lower payouts feed back into weaker bank credit and lending appetite, a mild financial-conditions tightener.
how we built this number — every step
The class rate is measured from our dated, sourced event library (decade-normalized Poisson — the full table is public at base_rates.json). The variant’s share within its class is the analyst’s editorial call, published so you can audit it. A wider range means thinner precedent. Full recipe: methodology · scored at Reality Check.
The butterfly cascade
How this trigger trickles across markets, left → right — the root shock, its first‑order moves, then the ripple effects. Drag any node; tap a market for its real price history.
Resolution timeline — how this probability is moving
Our model's odds (gold) over time vs the crowd's (Polymarket, blue), from the past toward the 1–3 years horizon. Each dot is a real macro event that nudged the probability — green pushed it up, red pushed it down. Tap a dot for the source. The gold path is an illustrative reconstruction anchored to today's estimate — real dated events, not a live re-estimate history.
What it would mean
If this plays out, it is a risk-off shock. Brussels imposes permanent windfall levy on bank net-interest income, European bank shares and dividends slashed. The trigger decomposes into signed root‑shocks — Credit spreads ▲ · Risk appetite ▼ — which propagate through our causal graph to the markets below.
If it happens — the markets it would move
Biggest moves first. Projected moves are cascade-model priors; hist A–B% = what comparable past events actually did (measured abnormal returns), and model prior · unmeasured marks markets with no analogue backing yet. Tap any market for its price history.
| Market | Class | Projected move | |
|---|---|---|---|
| 1 | MicroStrategy MSTRon Hyperliquid 📈 chart | Equity | ▼ -0.4% hist -4.44–+1.06% · other way +27.47% (n=12) |
| 2 | Solana SOLon Hyperliquid 📈 chart | Crypto | ▼ -0.3% hist -12.96–+0.71% · other way -1.04% (n=11) |
| 3 | Hyperliquid (HYPE) HYPEon Hyperliquid | Crypto | ▼ -0.3% model prior · unmeasured |
| 4 | High-yield credit HYG 📈 chart | Rate | ▼ -0.2% hist -0.49–+0.04% · other way -0.28% (n=12) |
| 5 | Ether ETHon Hyperliquid 📈 chart | Crypto | ▼ -0.2% hist -9.14–+1.96% · other way +4.87% (n=11) |
| 6 | Bitcoin BTCon Hyperliquid 📈 chart | Crypto | ▼ -0.2% hist -4.02–+1.33% · other way +6.05% (n=11) |
| 7 | Volatility (VIX) VIXon Hyperliquid 📈 chart | Vol | ▲ +0.2% hist -1.87–+4.0% · other way -0.58% (n=12) |
| 8 | Nasdaq 100 NDXon Hyperliquid 📈 chart | Index | ▼ -0.2% hist -0.71–+0.18% · other way +0.06% (n=12) |
| 9 | Financials XLF 📈 chart | Equity | ▼ -0.2% hist -0.11–+0.01% · other way +0.01% (n=12) |
| 10 | S&P 500 SPXon Hyperliquid 📈 chart | Index | ▼ -0.2% hist -0.27–+0.02% · other way +0.04% (n=12) |
| 11 | Tech sector XLK 📈 chart | Equity | ▼ -0.1% hist -0.19–+0.16% · other way +0.09% (n=12) |
Probable recommendation
Historical precedent — what analogous events actually did
Across 40 analogous events (overlap‑weighted), as abnormal returns — market beta stripped, so it's the event's own effect, not the market backdrop. Shown at 20 days (persistent) and 5 days (immediate); ↺ fades = the two horizons disagree. Confidence = consistency × sample × significance.
| Asset | History says | Abnormal (20d · 5d) | Hit | n | Confidence | vs cascade |
|---|---|---|---|---|---|---|
| SOL SOL | SHORT | -10.0% · 5d -7.8% | 83% | 20 | 0.42 | ✓ matches cascade |
| ETH ETH | SHORT | -7.8% · 5d -5.6% | 70% | 20 | 0.27 | ✓ matches cascade |
| High-yield credit HYG | SHORT | -0.3% · 5d +0.0% ↺ fades | 66% | 35 | 0.26 | ✓ matches cascade |
| MSTR MSTR | SHORT | -3.8% · 5d -3.3% | 65% | 37 | 0.25 | ✓ matches cascade |
| Gold XAU | LONG | +0.7% · 5d +0.2% | 61% | 37 | 0.20 | · |
| Bitcoin BTC | SHORT | -3.6% · 5d -2.1% | 60% | 21 | 0.15 | ✓ matches cascade |
| XLF XLF | LONG | +0.1% · 5d -1.0% ↺ fades | 56% | 37 | 0.11 | ⚠ differs |
| NDX NDX | SHORT | -0.6% · 5d -1.7% | 54% | 39 | 0.07 | ✓ matches cascade |
| 10y yield DGS10 | SHORT | -11bp · 5d -4bp | 52% | 40 | 0.04 | · |
| Volatility VIX | LONG | +3.8% · 5d +1.2% | 49% | 38 | 0.00 | ✓ matches cascade |
| SPX SPX | SHORT | -0.2% · 5d -0.1% | 37% | 40 | 0.00 | ✓ matches cascade |
| XLK XLK | LONG | +0.2% · 5d -0.7% ↺ fades | 47% | 37 | 0.00 | ⚠ differs |
| US dollar DXY | LONG | +0.2% · 5d +0.1% | 49% | 40 | 0.00 | · |
Why this probability
EU bank windfall levies already enacted ad hoc (Italy, Spain); permanent EU-wide less certain. A base‑rate‑anchored prior, continuously scored against what actually happens — not a forecast.