Rolling Returns
Glaxosmithkline Pharmaceuticals Ltd.
Every 15-year stretch GLAXO has been through — 61 of them, each starting a month after the last. The median returned 9.1% a year, the worst 6.6%, the best 12.8%. A single headline CAGR hides all of that.
Every Holding Period
A rolling window is every possible start date, not one. A five-year window starting in January is a different investment from one starting in February, and over twenty years there are a couple of hundred of them. What follows is the full spread of what each holding period actually produced.
Across 229 separate 1-year holding periods, the median returned 9.6% a year. The worst lost 32.1% a year and the best made 107.8%.
Worst start: April 2016 — -32.1% a year for the 1 years that followed.
Best start: May 2023 — 107.8% a year.
Against the Nifty 500: GLAXO came out ahead in 51.1% of the 229 windows both series cover.
Across 205 separate 3-year holding periods, the median returned 10.5% a year. The worst lost 13.9% a year and the best made 45.8%.
Worst start: March 2015 — -13.9% a year for the 3 years that followed.
Best start: January 2008 — 45.8% a year.
Against the Nifty 500: GLAXO came out ahead in 51.7% of the 205 windows both series cover.
Across 181 separate 5-year holding periods, the median returned 9.4% a year. The worst lost 4.6% a year and the best made 24.3%.
Worst start: March 2015 — -4.6% a year for the 5 years that followed.
Best start: December 2008 — 24.3% a year.
Against the Nifty 500: GLAXO came out ahead in 37.6% of the 181 windows both series cover.
Across 157 separate 7-year holding periods, the median returned 8.4% a year. The worst lost 3.5% a year and the best made 25.8%.
Worst start: April 2016 — -3.5% a year for the 7 years that followed.
Best start: January 2008 — 25.8% a year.
Against the Nifty 500: GLAXO came out ahead in 33.8% of the 157 windows both series cover.
Across 121 separate 10-year holding periods, the median returned 7.3% a year. Not one of them ended in a loss — the weakest still compounded at 2.5% a year.
Worst start: May 2013 — 2.5% a year for the 10 years that followed.
Best start: January 2008 — 14.2% a year.
Against the Nifty 500: GLAXO came out ahead in 25.6% of the 121 windows both series cover.
Across 61 separate 15-year holding periods, the median returned 9.1% a year. Not one of them ended in a loss — the weakest still compounded at 6.6% a year.
Worst start: May 2011 — 6.6% a year for the 15 years that followed.
Best start: May 2009 — 12.8% a year.
Against the Nifty 500: GLAXO came out ahead in 11.5% of the 61 windows both series cover.
Windows step forward one month at a time and are measured on month-end adjusted closing prices, so dividends are treated as reinvested. Overlapping windows share months by construction — that is what makes the spread a description of this stock's history rather than a sample of independent trials.
Against The Index
Beating an index once is a result. Beating it across most of the periods an investor could have picked is a pattern. Over 15-year windows, GLAXO finished ahead of the Nifty 500 in 11.5% of the 61 periods both series cover.
1-year windows
Ahead in 51.1% of 229 periods.
3-year windows
Ahead in 51.7% of 205 periods.
5-year windows
Ahead in 37.6% of 181 periods.
7-year windows
Ahead in 33.8% of 157 periods.
10-year windows
Ahead in 25.6% of 121 periods.
15-year windows
Ahead in 11.5% of 61 periods.
Each window is compared against the index over the identical calendar months, on the same adjusted basis — not against an assumed rate of return.
How This Is Calculated
Windows step forward one month at a time, so they share most of their months with each other. That is what makes this a description of GLAXO's actual history rather than a set of independent trials — and why the spread should not be read as a probability.
Measured on month-end closing prices adjusted for dividends and splits, so dividends count as reinvested. A window that opened or closed mid-month would differ a little in either direction.
GLAXOis in today's Nifty 500 universe. Companies that delisted or collapsed are not on this site at all, so the worst outcome shown here is the worst among the survivors.
Measured on data to 2026-08-31, from 2006-08-01. Full definitions are on our methodology page.
HELP CENTER
Everything you need to know about this page and the data presented.
Over 15 years, Glaxosmithkline Pharmaceuticals Ltd. has been through 61 separate 15 years holding periods — one starting every month. The median returned 9.1% a year, the worst 6.6% and the best 12.8%. A rolling return measures every possible start date instead of one, which is why it answers a question a single headline CAGR cannot: how much the outcome depended on when you happened to buy.
No — not in any of the 121 10 years periods the record covers. The weakest of them still compounded at 2.5% a year. That is a statement about the past, not a guarantee about any future 10 years, and it is measured only over the years Glaxosmithkline Pharmaceuticals Ltd. has been listed.
-4.6% a year, for the five years beginning March 2015. For contrast the best 5 years returned 24.3% a year, starting December 2008, and the median across all 181 periods was 9.4%. The gap between those two numbers is the part of the outcome that came down to timing rather than to the company.
On this record, yes. 1 year outcomes ranged from -32.1% to 107.8% a year — a spread of 139.9%. 15 years outcomes ranged from 6.6% to 12.8%, a spread of 6.2%. Longer holding periods narrowed the range of results, which is the usual pattern and the reason this page publishes every window rather than one. Narrowing the range is not the same as removing the risk.
In 11.5% of the 61 15 years periods both series cover. Each window is compared against the index over the identical months, not against an assumed index return, so the comparison is a like-for-like record rather than a model.
Windows step forward one month at a time on month-end closing prices adjusted for dividends and stock splits, so dividends are treated as reinvested. A window length is only published once there are at least twelve complete windows behind it — fewer than that describes an anecdote, not a distribution. Overlapping windows share months by construction, which is what makes this a description of the actual history of Glaxosmithkline Pharmaceuticals Ltd. rather than a sample of independent trials. Companies that delisted are not on this site at all, a survivorship bias worth holding in mind.
That is not a question this page answers, and we do not make recommendations. What it can show you is the full range of what every holding period in the listed history of Glaxosmithkline Pharmaceuticals Ltd. actually produced — including the worst ones, which most performance figures leave out. Those are records of what happened, not forecasts. A stock that never had a losing decade may still have one, and holding a single company is a materially different risk from holding an index.
Explore Further
GLAXO drawdowns and all-time high
The worst fall on record, how long recovery took, and how far the price sits below its peak.
GLAXO SIP returns
What a monthly investment would have produced, backtested rather than assumed.
GLAXO overview
Price history, wealth journey and how it compares with the index.
Rolling returns for every stock
Run the same question against any company we track.
ReturnScreener is an educational research platform and is not a SEBI-registered investment adviser. Everything on this page is a record of what historical prices did, not a projection and not a recommendation. Past performance does not guarantee future returns. See our methodology and disclaimer.