BIIB monthly performance report
Monthly BIIB research: returns, drawdown, relative strength, seasonality, and key stats.
BIIB monthly report
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Key takeaways
- Biogen (BIIB) closed September 2026 at $220.83, up 1.93% for the month and +57.80% over the trailing 12 months.
- Year-to-date, BIIB is +25.48%, outperforming the S&P 500 which has returned +12.94% YTD.
- The stock is trading +16.11% versus its 200-day moving average ($190.20), a bullish technical signal.
- Over the past three years, BIIB has underperformed the S&P 500 by −88.05%, with a relative strength index reading of 48.4.
- Win rate over the trailing 39 months stands at 41% — 16 positive months versus 23 negative months.
Biogen ended September 2026 at $220.83, posting a monthly return of +1.93%. The S&P 500 returned +0.41% over the same window, leaving relative performance at +1.52%.
The current quarter stands at +1.71% (Q3 2026 (QTD)), while medium-term trend remains constructive: price is +16.11% versus the 200-day moving average ($190.20).
Year-to-date, BIIB is +25.48% against SPY +12.94%, a gap of +12.53%. The stock is currently −2.11% below its 52-week high, with maximum 3-year drawdown at −57.68%.
| Period | BIIB | S&P 500 (SPY) | Excess return |
|---|---|---|---|
| 1 Day | −0.83% | +0.66% | −1.48% |
| 1 Week | −0.11% | −0.12% | +0.01% |
| 1 Month | +1.93% | +0.41% | +1.52% |
| 3 Months | +16.95% | +2.11% | +14.83% |
| 6 Months | +17.43% | +13.21% | +4.22% |
| YTD | +25.48% | +12.94% | +12.53% |
| 12 Months | +57.80% | +18.65% | +39.15% |
| 3 Years | −17.34% | +70.70% | −88.05% |
| Rank | Month | Return |
|---|---|---|
| #1 | Nov 2025 | +18.55% |
| #2 | Jun 2026 | +11.08% |
| #3 | Dec 2023 | +10.61% |
| #4 | Oct 2025 | +9.55% |
| #5 | May 2025 | +7.83% |
| Rank | Month | Return |
|---|---|---|
| #1 | Feb 2024 | −11.58% |
| #2 | Apr 2025 | −11.49% |
| #3 | Oct 2024 | −10.59% |
| #4 | Jul 2024 | −7.87% |
| #5 | Nov 2024 | −7.50% |
| Quarter | Return |
|---|---|
| Q2 2025 | −7.51% |
| Q3 2025 | +10.17% |
| Q4 2025 | +26.87% |
| Q1 2026 | +5.77% |
| Q2 2026 | +18.87% |
| Q3 2026 (QTD) | +1.71% |
| Year | Return |
|---|---|
| 2023 | −6.30% |
| 2024 | −41.16% |
| 2025 | +15.97% |
| 2026 | +27.87% |
| Metric | Value |
|---|---|
| 52-Week High | $225.59 (2026-09-02) |
| 52-Week Low | $131.52 (2025-08-29) |
| Current Price | $220.83 |
| 200-Day Moving Average | $190.20 |
| Price vs 200DMA | +16.11% |
| 3-Year Maximum Drawdown | −57.68% (2025-04-10) |
| Current Drawdown from 52W High | −2.11% |
| RS metric | Value |
|---|---|
| RS Index (3-year, rebased to 100) | 48.4 |
| 3-Year Excess Return vs S&P 500 | −88.05% |
| RS Peak | 103.7 (Oct 2023) |
| RS Trough | 32.9 (Jul 2025) |
| Status | Underperforming Benchmark |
Frequently asked questions
What was BIIB's return for this report period?
BIIB returned +1.93% in the latest monthly window ending 2026-09-04.
Has BIIB outperformed SPY year to date?
YTD BIIB: +25.48% vs SPY: +12.94%.
What is BIIB's 12-month return?
+57.80% over the trailing 12 months.
Is BIIB above or below its 200-day moving average?
Price is +16.11% versus 200DMA ($190.20).
What is the maximum drawdown in the 3-year window?
−57.68% on 2025-04-10.