All charts and data below are CPI-U inflation-adjusted and with dividends reinvested. (Why?)

Total Real Returns

BIIB: Total Real Return Chart (Dividends Reinvested, Inflation Adjusted)

BIIB real return snapshot: after CPI-U inflation, BIIB returned +49.22% over the past year and +17.99% YTD, with dividends reinvested. Since Sep. 17, 1991, BIIB is up +2,708.04% in real purchasing-power return, or +10.02%/yr, and is currently −68.28% below its real total-return high on Mar. 20, 2015.

Data ending Thu Aug. 20, 2026

Growth of $10,000

Tue 1991-09-17💬 to Thu 2026-08-20 Overall
Return
Exponential
Trendline
BIIB
×
+2,708.04%
+10.02%/yr
+15.35%/yr
R2=0.724
Biogen Inc NASDAQ Common Stock

Growth of $10,000 Summary

Tue 1991-09-17💬 to Thu 2026-08-20 Start
Value
End
Value
BIIB
×
$10,000.00
1991-09-17
$280,803.69
2026-08-20

This Year’s Performance

through 2026-08-20

  YTD YoY
BIIB
×
+17.99% +49.22%

Drawdowns

  Current
Drawdown
Worst
Drawdown
BIIB
×
−68.28%
on 2026-08-20
from 2015-03-20 peak
−90.83%
on 1994-12-16
from 1991-10-16 peak

Rolling Returns

Period ending Thu 2026-08-20 1 yr 2 yr 3 yr 5 yr 10 yr
BIIB
×
+49.22% −1.86%
−0.94%/yr
−24.80%
−9.06%/yr
−48.74%
−12.51%/yr
−51.30%
−6.94%/yr

Annual Returns

Year BIIB
2026 (YTD) +17.99%
2025 +12.09%
2024 −42.56%
2023 −9.58%
2022 +8.41%
2021 −8.46%
2020 −18.59%
2019 −3.60%
2018 −7.31%
2017 +10.01%
2016 −9.31%
2015 −10.41%
2014 +20.51%
2013 +88.17%
2012 +30.74%
2011 +59.40%
2010 +23.48%
2009 +9.35%
2008 −16.40%
2007 +11.16%
2006 +5.97%
2005 −34.28%
2004 +75.78%
2003 +8.60%
2002 −53.00%
2001 +7.43%
2000 +86.61%
1999 +307.16%
1998 +34.56%
1997 +42.32%
1996 +17.88%
1995 +794.81%
1994 −64.00%
1993 −36.04%
1992 −34.59%
1991 −31.15%