BIIB chart · All upcoming earnings
| Move | Mean | Median | Std dev | Hit rate |
|---|---|---|---|---|
| Day 1 | +1.6% | +1.1% | 3.8% | 60% |
| Day 2 | -0.1% | -0.2% | 3.0% | 50% |
| Day 3 | -1.0% | -1.3% | 1.9% | 20% |
| 5-day | +1.6% | +0.7% | 5.3% | 60% |
Day 1 = the close-to-close move on the first session to trade the news — hover for the EPS surprise.
| Report | Est | Actual | Surprise | Gap | 1-day | +5d | +1mo |
|---|---|---|---|---|---|---|---|
| 2026-07-29 beat | 2.03 | 3.60 | +77.4% | +2.4% | +1.8% | -1.2% | +5.9% |
| 2026-04-29 beat | 2.95 | 3.57 | +20.9% | -0.1% | +6.0% | -1.9% | +0.8% |
| 2026-02-06 beat | 1.62 | 1.99 | +23.2% | +0.9% | +8.5% | -2.3% | -6.3% |
| 2025-10-30 beat | 3.88 | 4.81 | +23.9% | -5.2% | +1.2% | +4.8% | +18.8% |
| 2025-07-31 beat | 3.88 | 5.47 | +41.0% | +5.0% | +1.1% | -0.2% | +3.3% |
| 2025-05-01 beat | 2.95 | 3.02 | +2.4% | -0.6% | -0.1% | -2.1% | +8.4% |
| 2025-02-12 beat | 3.36 | 3.44 | +2.3% | -1.9% | -4.3% | +2.7% | +4.5% |
| 2024-10-30 beat | 3.79 | 4.08 | +7.8% | +0.6% | -1.2% | -3.7% | -11.3% |
| 2024-08-01 beat | 4.03 | 5.28 | +31.0% | +1.2% | -1.2% | -3.1% | -2.8% |
| 2024-04-24 beat | 3.46 | 3.67 | +6.0% | +3.0% | +4.6% | +7.0% | +8.0% |
“1-day” is the close-to-close move over the session that first traded on the news (the next session for after-close reports). “+5d / +1mo” are the further drift from that close.
Earnings dates & estimates from Yahoo Finance (refreshed 2026-09-13); price reactions from end-of-day data. History, not a forecast. Not investment advice.