BIIB monthly performance report
Explore BIIB's monthly returns, drawdown, and seasonality trends — updated every month.
BIIB monthly report
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Key takeaways
- Biogen (BIIB) closed September 2026 at $215.50, down 0.53% for the month and +49.85% over the trailing 12 months.
- Year-to-date, BIIB is +22.45%, outperforming the S&P 500 which has returned +11.70% YTD.
- The stock is trading +12.05% versus its 200-day moving average ($192.32), a bullish technical signal.
- Over the past three years, BIIB has underperformed the S&P 500 by −86.62%, with a relative strength index reading of 49.6.
- Win rate over the trailing 39 months stands at 38.5% — 15 positive months versus 24 negative months.
Biogen ended September 2026 at $215.50, posting a monthly return of −0.53%. The S&P 500 returned −0.70% over the same window, leaving relative performance at +0.17%.
The current quarter stands at −0.26% (Q3 2026 (QTD)), while medium-term trend remains constructive: price is +12.05% versus the 200-day moving average ($192.32).
Year-to-date, BIIB is +22.45% against SPY +11.70%, a gap of +10.75%. The stock is currently −4.47% below its 52-week high, with maximum 3-year drawdown at −57.68%.
| Period | BIIB | S&P 500 (SPY) | Excess return |
|---|---|---|---|
| 1 Day | −1.62% | −0.12% | −1.50% |
| 1 Week | −0.76% | −0.34% | −0.42% |
| 1 Month | −0.53% | −0.70% | +0.17% |
| 3 Months | +10.17% | +2.80% | +7.37% |
| 6 Months | +18.70% | +13.85% | +4.85% |
| YTD | +22.45% | +11.70% | +10.75% |
| 12 Months | +49.85% | +15.01% | +34.84% |
| 3 Years | −14.92% | +71.69% | −86.62% |
| Rank | Month | Return |
|---|---|---|
| #1 | Nov 2025 | +18.03% |
| #2 | Dec 2023 | +10.55% |
| #3 | Jun 2026 | +10.23% |
| #4 | Oct 2025 | +10.13% |
| #5 | May 2025 | +7.19% |
| Rank | Month | Return |
|---|---|---|
| #1 | Feb 2024 | −12.03% |
| #2 | Apr 2025 | −11.52% |
| #3 | Oct 2024 | −10.24% |
| #4 | Jul 2024 | −8.03% |
| #5 | Nov 2024 | −7.68% |
| Quarter | Return |
|---|---|
| Q2 2025 | −8.22% |
| Q3 2025 | +11.54% |
| Q4 2025 | +25.64% |
| Q1 2026 | +4.17% |
| Q2 2026 | +17.85% |
| Q3 2026 (QTD) | −0.26% |
| Year | Return |
|---|---|
| 2023 | −6.55% |
| 2024 | −40.91% |
| 2025 | +15.09% |
| 2026 | +22.45% |
| Metric | Value |
|---|---|
| 52-Week High | $225.59 (2026-09-02) |
| 52-Week Low | $135.39 (2025-09-29) |
| Current Price | $215.50 |
| 200-Day Moving Average | $192.32 |
| Price vs 200DMA | +12.05% |
| 3-Year Maximum Drawdown | −57.68% (2025-04-10) |
| Current Drawdown from 52W High | −4.47% |
| RS metric | Value |
|---|---|
| RS Index (3-year, rebased to 100) | 49.6 |
| 3-Year Excess Return vs S&P 500 | −86.62% |
| RS Peak | 107.6 (Oct 2023) |
| RS Trough | 34.2 (Jul 2025) |
| Status | Underperforming Benchmark |
Frequently asked questions
What was BIIB's return for this report period?
BIIB returned −0.53% in the latest monthly window ending 2026-09-18.
Has BIIB outperformed SPY year to date?
YTD BIIB: +22.45% vs SPY: +11.70%.
What is BIIB's 12-month return?
+49.85% over the trailing 12 months.
Is BIIB above or below its 200-day moving average?
Price is +12.05% versus 200DMA ($192.32).
What is the maximum drawdown in the 3-year window?
−57.68% on 2025-04-10.