Biogen (BIIB) — Daily Price Character
Historical session stats from dividend-adjusted prices: win rate, streaks, record days, weekday patterns, and (when available) how often the stock was green on S&P 500 green days.
BIIB
Archetype
Explosive
High daily volatility — frequent large price swings.
Win rate
48.1%
4182 green · 4169 red · 348 flat · 8699 sessions
Current streak
1 green
As of Apr 7, 2026
Max win / lose streak
12 / 10 days
Win streak return: +15.20% · Lose: 12.15%
Median / σ daily
+0.000% · 3.532%
Avg green +2.41% · avg red 2.20%
Extreme days (>3%)
23.1%
1017 up · 988 down
History from Sep 18, 1991 through Apr 7, 2026 · 8699 trading days with returns.
Trailing year — daily returns (calendar)
Apr 8, 2025 – Apr 7, 2026 · Mon–Fri sessions only
Monday–Friday — average return
Average dividend-adjusted return on that weekday (green / red by sign). Green/red day rule: ±0.01% vs prior close.
Monday–Friday — win rate
Share of sessions that closed green on that weekday. Bars are green at or above 50%, red below 50%.
Top green days
Largest single-session gains (dividend-adjusted), by historical return.
| Date | Return |
|---|---|
| Nov 4, 2020 | +43.97% |
| Sep 28, 2022 | +39.85% |
| Jun 7, 2021 | +38.34% |
| Apr 20, 1999 | +27.35% |
| Aug 3, 1993 | +26.67% |
| Mar 13, 1996 | +26.62% |
| Aug 10, 1995 | +26.47% |
| Oct 22, 2019 | +26.11% |
| Mar 16, 1995 | +24.14% |
| Nov 1, 1995 | +22.22% |
| Aug 4, 1993 | +21.05% |
| Jan 21, 2000 | +20.42% |
| Feb 18, 2004 | +20.27% |
| Jul 6, 2018 | +19.63% |
| Dec 22, 1999 | +19.24% |
| May 10, 1993 | +18.86% |
| Oct 15, 2007 | +18.84% |
| Jul 26, 1993 | +18.75% |
| Dec 22, 1995 | +18.62% |
| Jan 8, 1992 | +18.18% |
Worst red days
Largest single-session losses; "Days to recovery" counts trading sessions until close recovered the prior peak (dividend-adjusted).
| Date | Return | Days to recovery |
|---|---|---|
| Feb 28, 2005 | 42.55% | 644 |
| Mar 21, 2019 | 29.23% | 221 |
| Aug 1, 2008 | 28.31% | 649 |
| Nov 9, 2020 | 28.17% | 143 |
| Dec 13, 2007 | 23.68% | 837 |
| Jul 24, 2015 | 22.08% | 1477 |
| Feb 2, 2000 | 20.27% | 14 |
| Nov 15, 1991 | 20.13% | 35 |
| Apr 7, 1992 | 19.62% | 140 |
| Apr 20, 2000 | 18.42% | 15 |
| Jul 28, 1994 | 17.39% | 13 |
| Jun 11, 2002 | 16.52% | 24 |
| Apr 6, 1992 | 15.96% | 167 |
| Jul 5, 1996 | 15.17% | 32 |
| Jul 12, 2001 | 15.16% | 77 |
| Nov 13, 2000 | 15.11% | 17 |
| Apr 20, 1992 | 15.04% | 1 |
| Aug 31, 1998 | 15.01% | 3 |
| Mar 29, 2000 | 14.86% | 56 |
| Sep 10, 1999 | 14.83% | 39 |
Frequently asked questions
What is the daily win rate for Biogen (BIIB)?
- Historically, Biogen (BIIB) closed green on 48.1% of trading days (4182 green, 4169 red, 348 flat), using dividend-adjusted closes and a ±0.01% threshold for green vs red.
What is the current winning or losing streak for Biogen (BIIB)?
- As of 2026-04-07, Biogen (BIIB) is on a 1-day winning streak (consecutive green or red days by the same rules, ignoring trailing flat days).
What does Steady, Balanced, or Explosive mean for Biogen (BIIB)?
- We label Biogen (BIIB) as "explosive" based on the sample standard deviation of daily returns: High daily volatility — frequent large price swings.
What were the best and worst single trading days for Biogen (BIIB)?
- Largest single-day gain: +43.97%. Largest single-day loss: 42.55%. Tables on this page list the top record green and red days.
What counts as an "extreme" daily move for Biogen (BIIB)?
- We treat a day as extreme if the absolute dividend-adjusted daily return exceeds 3%. About 23.1% of trading days for Biogen (BIIB) were extreme (1017 up, 988 down).
Data & methodology
How are green, red, and flat days defined?
- We use dividend-adjusted (or close-to-close for non-equity) daily returns. Green: return ≥ +0.01%. Red: return ≤ −0.01%. Flat: between those bounds.
How is the current streak calculated?
- We count consecutive green or consecutive red days using the same thresholds. If the most recent session is flat, we skip trailing flat days and measure from the last non-flat close.
What does “vs S&P 500” mean?
- On sessions where the S&P 500 (^GSPC) was green, we report how often this stock was also green. Shown only for USD equities when benchmark data exists and the symbol is not the index itself.
Where does the archetype come from?
- Sample standard deviation of daily returns: low → Steady, high → Explosive, otherwise Balanced. Labels describe typical daily volatility, not quality of the investment.