Trump imposes 50% tariffs on wide range of Canadian goods under Section 388
Measured from 21 Jul 2026 (event start), not the 21 Jul 2026 announcement
Semiconductors moved -6.8%, the largest reaction measured, though not statistically significant, meaning it may reflect normal market noise rather than the event itself. This is a provisional result; the full measurement window is not yet complete.
NVDA, AMD, INTC · down
What Happened
President Trump signed an executive order imposing 50 percent tariffs on a broad range of Canadian exports, citing alleged unfair Canadian trade practices in automobiles, alcohol, and dairy products. The order invokes Section 388 of trade law and applies to CUSMA-compliant goods, meaning it supersedes existing trade agreement protections. The administration specifically cited Quebec-produced goods and Canadian discrimination against American commerce. Implementation is set for approximately one month out, giving markets and trade negotiators a window for retaliation or deal-making. This escalates the recurring U.S.-Canada trade dispute beyond previous rounds and raises the prospect of retaliatory tariffs on U.S. exports.
50 percent tariffs on Canadian goods reignite U.S.-North America trade war with broad cross-sector exposure, threatening auto supply chains, commodity pricing, and currency dynamics; retaliatory risk creates two-way demand shock.
Signed July 21, 2026; implementation expected approximately August 21, 2026
Executive order signed July 21, 2026 with implementation scheduled one month forward (approximately August 21, 2026). The tariff threat was announced and formalized on this date.
Read how dates work →Partial reaction shown. Significance flags are marked provisional and may change as more price data accumulates.
How To Read This
Each sector below is a basket of named stocks. The percentage shown is the move beyond the overall market (S&P 500) , what event studies call the . A move only counts as when it sits clearly outside that basket's normal weekly swings.
How Much Sectors Moved
Path over time. Click a sector in the legend to toggle it. Dashed lines mark key moments.
Semiconductors moved most at -6.8% against the market, the direction you would expect from a tariffs. None of the moves cleared the significance threshold. Read the direction as flavour, not signal.
Volatility
Volatility measures how erratic prices became, a separate signal from the direction of the move.
Market fear rose modestly
- Industrials29% → 34%1.2x more volatile after
- Semiconductors54% → 84%1.5x more volatile after
- Retailers27% → 27%volatility roughly unchanged
- Broad market12% → 16%1.4x more volatile after
The VIX rose 6.0 percent across the window, a mild move. Read this as the market's demand for protection, not the direction of any single sector.
A ratio above 1.00 means the sector's daily-price swings widened after the event. Semiconductors became the most erratic at 1.54×, and 3 of 4 sectors traded meaningfully wider than they did before. Volatility is a separate signal from direction: a sector can end flat and still have traded wildly along the way.
Phases
| Sector | Peak Move | Peak Day | Reverted By |
|---|---|---|---|
| Industrials | -2.9% | Day 0 | Day 1 |
| Semiconductors | -13.5% | Day 6 | Day 7 |
| Retailers | +6.5% | Day 6 | Day 7 |
| Broad market | -0.0% | Day -3 | Day -1 |
The reaction peaked around day 2 on average. 4 of 4 sectors reverted inside the window. A reaction that reverts is a shock priced in; one that stays is a re-rating.
Historical Precedents
Companies Most Affected
Measured 10 days after the event. Reaction still developing; the full window is not yet complete.
This tool informs your decision. It does not give investment advice.