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Why Blending Matters

Why your best performing series might be your biggest risk

The S&P 500 returned roughly 10% annually over the thirty years from 1993 to 2023. It also fell 57% between October 2007 and March 2009.

That is not a contradiction. It is the part of the story that return figures leave out.


The number that return charts never show

When you look at a ten-year performance chart, you see a line moving upward. You see an annualised return. You might see a comparison against a benchmark.

What you do not see is how far that line fell at its worst point — and how long it took to come back.

A portfolio that returned 10% annually over twenty years but fell 60% in a single period is a very different investment experience from one that returned 8% annually with a maximum decline of 20%. The return figures look comparable. The experience of holding through them is not.

The number that captures this difference is called drawdown: how far a portfolio has fallen from its previous peak at any point in time.

A portfolio that reached a value of 150 and is now at 120 is in a 20% drawdown — even if 120 is higher than where it started. Drawdown is measured from peak, not from the starting point. That distinction matters because it reflects the actual experience of an investor who was fully invested at the top.

Illustrative NAV series — hover over the chart to explore each episode

Episode 1 — Deep & Long
Depth 58%Fall time 8 monthsRecovery 29 monthsTotal episode37 months
Episode 2 — Sharp & Fast
Depth 20%Fall time 5 monthsRecovery 6 monthsTotal episode11 months
Recovery always takes longer than the fall. In every episode above, the recovery bracket is longer than the fall bracket — often by 3 to 5×.

What actually happened to investors in 2008

The S&P 500’s 57% drawdown between 2007 and 2009 is the clearest modern example of why drawdown matters more than return when assessing long-term risk.

An investor who put $100,000 into an S&P 500 index fund in late 2007 watched it fall to roughly $43,000 by March 2009. Not a paper loss in the background — a visible, real decline in the balance they could see every time they logged in.

The full recovery took until April 2013. Over four years of holding through a position that had lost more than half its value.

Research consistently shows that most investors do not hold through declines of that magnitude. They sell. They lock in the loss. They miss the recovery. The 10% annual return figure assumes continuous holding — which is exactly what the drawdown makes psychologically difficult.

The same pattern played out across global markets. The FTSE 100 fell over 45% during the same period. European, Asian, and Australian equity indices all saw comparable declines. This was not a US event — it was a simultaneous global drawdown that tested every investor holding equities regardless of geography.


Why drawdown is harder to recover from than it looks

There is a mathematical reason drawdown is so damaging — and most investors never see it clearly until it is too late.

When a portfolio falls, the recovery required to get back to even is always larger than the decline. Not slightly larger. Significantly larger. And the relationship is not linear — it accelerates sharply as the drawdown deepens.

A 10% decline needs an 11.1% gain to recover. Uncomfortable but manageable. A 30% decline needs a 42.9% gain. A 50% decline needs a 100% gain — you need to double your money just to get back to where you started. A 60% decline, which is what the S&P 500 experienced in 2008, requires a 150% gain.

Drag the slider below to see the recovery required for any drawdown depth:

Your drawdown
50%
Return needed to break even
+100.0%
Catastrophic. You need to double your money just to get back to where you started.
At 10% drawdown: 11.1% return needed. At 30%: 42.9%. At 50%: 100%. At 70%: 233%.
DrawdownReturn to break evenWhat it takes
5%+5.3%Routine — happens in normal market conditions
10%+11.1%A bad quarter — recoverable within a year
20%+25.0%A difficult year — patience required
30%+42.9%A serious crisis — multiple years to recover
40%+66.7%Severe — most investors begin to doubt
50%+100.0%Catastrophic — you need to double your money
60%+150.0%Generational event — recovery takes years
70%+233.3%Almost unsurvivable for most investors

This is why the psychological pressure during a drawdown is not proportional to the percentage decline. Each step deeper makes recovery feel progressively more out of reach — because mathematically, it is.

An investor watching a 30% decline may still believe in recovery. The same investor at 50% is staring at a number that requires a full doubling of their remaining capital. At that point, the rational argument for holding and waiting — which is almost always the correct one — becomes almost impossible to act on emotionally.

This is the hidden cost of deep drawdown that return charts never show. The annual return figure tells you what the investment delivered over time. It does not tell you whether a typical investor could hold through the drawdown phase long enough to actually receive that return.


High return and high drawdown often come together

This is the uncomfortable truth about performance-chasing: the series with the highest historical return frequently comes with the deepest historical drawdown.

That is not a coincidence. Higher return potential typically reflects higher volatility, which means larger swings in both directions. A high-growth equity index can compound impressively over decades precisely because it is willing to fall sharply during contractions — and recover over time.

The question is not whether a series has ever fallen sharply. Almost every high-return series has. The question is: could you stay invested through a 40% or 50% drawdown that lasted two or three years?

If the honest answer is no — if you would sell, reduce your position, or stop contributing at some point during that decline — then the published historical return figure is not actually achievable for you, regardless of how accurate it is.

Your real return is bounded by your ability to hold through the worst drawdown period.


Duration matters as much as depth

A drawdown episode has two dimensions that both matter: depth (how far it fell) and duration (how long the complete cycle lasted — from the start of the decline, through the lowest point, to full recovery).

The COVID crash of March 2020 produced a roughly 34% peak-to-trough decline on the S&P 500 — deep by any measure. But the full recovery took approximately five months. An investor who held through it was back to even by August 2020.

The 2008 episode was shallower in speed but vastly longer in duration. A 57% decline followed by a four-year recovery. The total episode — decline plus recovery — lasted over five years for US equities.

These two episodes look similar on a return chart over a long enough period. On a drawdown episode table they look completely different. The 2020 episode was recoverable for most investors who held their nerve for a few months. The 2008 episode required sustained discipline across years of uncertainty.

Duration is often the harder number to face. A 20% decline that lasts six months is difficult. A 20% decline that lasts three years tests something different — the investor’s ability to continue holding while the recovery date remains unknown.

The two episodes side by side make this concrete:

EpisodeYearIndexPeak-to-trough declineRecovery timeTotal episode length
Global financial crisisOct 2007 – Mar 2009S&P 500−57%~4 years~5.5 years
Global financial crisisJun 2007 – Mar 2009FTSE 100−48%~5 years~6 years
Global financial crisisJan 2008 – Mar 2009Nifty 50−60%~18 months~2.5 years
COVID crashFeb 2020 – Mar 2020S&P 500−34%~5 months~8 months
COVID crashJan 2020 – Mar 2020FTSE 100−35%~18 months~2 years
COVID crashJan 2020 – Mar 2020Nifty 50−38%~6 months~9 months
Depth (%) — left axisFall time (months) — right axisRecovery time (months) — right axis
2008 S&P 500: depth 57%, fall 17m, recovery 48m. 2008 FTSE 100: depth 48%, fall 16m, recovery 60m. 2008 Nifty 50: depth 60%, fall 12m, recovery 18m. 2020 S&P 500: depth 34%, fall 1m, recovery 5m. 2020 FTSE 100: depth 35%, fall 2m, recovery 18m. 2020 Nifty 50: depth 38%, fall 2m, recovery 6m.
Same crisis, different recovery. The Nifty 50 fell deeper than the S&P 500 in 2008 but recovered nearly 3× faster. Depth and duration tell different stories.

Look at any row and notice one pattern that holds every time: the recovery always takes longer than the fall.

The S&P 500 fell 57% over roughly 17 months in 2008. It took 4 years to recover — nearly three times as long as the decline. The COVID crash on the S&P 500 fell 34% in about 5 weeks. Recovery took 5 months — still four times the length of the fall. Even the fastest recovery in the table, Nifty 50 in 2020, took roughly 6 months to recover from a decline that arrived in under 6 weeks.

Markets fall fast and recover slowly. That asymmetry is not a quirk of these specific episodes — it is a structural feature of how drawdowns work. Panic compresses prices quickly. Confidence rebuilds gradually.

This matters practically: an investor who decides to wait out the decline and re-enter “when things stabilise” is almost always making that decision near the bottom, then watching a slow recovery from the sidelines. The fall feels like an event. The recovery feels like waiting.

2008 tells one more story worth noting. The Nifty 50 fell 60% — deeper than the S&P 500 — but recovered in roughly 18 months, faster than US or UK equities. An Indian investor who held through 2008 was back to even well before their US or UK counterpart. Same global crisis, same severity of decline, meaningfully different recovery experience.

None of this shows up in a return chart. It shows up in a drawdown episode table.


What to do with this

Understanding drawdown history does not tell you what a series will do in the future. Past drawdowns describe what investors experienced holding through these periods — they are a record of actual events, not a prediction of what comes next.

What they do tell you is whether the historical behaviour of a series is compatible with how you would actually respond during a decline of that magnitude.

A series with a maximum historical drawdown of 55% and a recovery period of four years is not a bad investment by definition. It may be exactly right for an investor with a twenty-year horizon, high risk tolerance, and the discipline to hold. The same series is the wrong choice for an investor who would sell after a 25% decline.

Knowing your own drawdown history — in actual numbers, not approximations — is the starting point for making that judgement honestly.


See your own drawdown history

PortBlend’s Drawdown Dynamics analysis takes any NAV series — upload a CSV with a date column and a value column — and produces a complete drawdown history: a stats summary showing max drawdown, average drawdown, and episode count; a stress heatmap showing which calendar periods were worst; a timeline chart; and a full episode table with depth, duration, and recovery status for every drawdown episode in the series.

A NAV series can be anything that represents a value tracked day by day. It can be as simple as the daily closing price of an index or ETF, freely available from any financial data site. It can be a portfolio valuation you track in a spreadsheet. Or it can be the output of a systematic trading strategy built on indicators and buy/sell rules — the same format works regardless of what generated the numbers. If it has a date and a daily value, PortBlend can analyse it.

Upload your own NAV series to PortBlend and see your actual drawdown history — free, no account needed.


Disclaimer: Historical drawdown and performance analysis is shown for illustrative and educational purposes only. Past drawdown history describes what investors experienced holding through these periods. It does not predict future behavior.