Investing and market evidence
52 articles
Active and Passive Investing, and the Arithmetic Underneath the Argument
Most of this debate is conducted with performance statistics that are contested and hard to obtain. Underneath it sits an argument that needs no statistics at all — it follows from the fact that everybody's holdings add up to the whole market. Knowing what that argument does and does not establish is worth more than any table.
4 min read · Updated 10 September 2026
The Advantages and the Real Risks of Index Investing
The case for indexing is strong and mostly correct. It is also usually presented as though the approach had no risks of its own, which is not true — and the risks it does have are unusual, because they come from the rulebook rather than from anybody's judgement.
4 min read · Updated 10 September 2026
CAGR and XIRR — Which One Answers Your Question
Two ways of turning an investment into a single annual rate, suited to two different situations. Using the wrong one does not produce a slightly-off answer; it produces a number that is not measuring your money at all. The rule for choosing between them takes one sentence.
4 min read · Updated 10 September 2026
How to Work Out What Your Monthly Investing Has Actually Returned
Your money went in on many dates and each instalment has been invested for a different length of time. That makes the return a slightly awkward calculation and a very easy one to get wrong — and the two most popular wrong ways go in opposite directions, so people sometimes make both and feel reassured.
4 min read · Updated 10 September 2026
Can a Mutual Fund Fail — and What Protections Do Investors Actually Have?
A fund cannot go bankrupt and run off with your money, because of how it is structured. But it can lose value, freeze your withdrawals, or wind itself up while you are still in it — and those are different risks with different protections.
6 min read · Updated 9 September 2026
Combining Broad Market Indices Without Fooling Yourself
Holding several index funds feels like more diversification and frequently is not, because the indices contain the same companies. Working out what a second index actually adds takes one question, and the answer decides whether you have built a portfolio or an expensive way of owning what you already had.
4 min read · Updated 10 September 2026
How to Compare Two Investments Fairly
Almost every unfair comparison you will be shown is unfair in one of five specific ways, and none of them requires anyone to state a false number. This is the checklist — five things that must be held constant, and what happens to the answer when each one is not.
4 min read · Updated 10 September 2026
How Data Mining and Backtest Overfitting Mislead Investors
Try enough investment rules against past data and one of them will look brilliant. That is not evidence it works — it is what happens when you go looking, and the demonstration below takes one table to show.
4 min read · Updated 2 September 2026
Holding Shares Directly, or Holding a Fund
The comparison is usually framed as skill against convenience, which flatters both sides and settles nothing. The differences that actually decide it are structural — what happens when one holding fails, what the work costs you, and what tax does to the money you never intended to spend.
4 min read · Updated 10 September 2026
Direct and Regular Plans — the Same Fund at Two Prices
Two versions of one scheme, holding the identical portfolio, run by the same manager, differing only in whether a distributor is being paid out of your returns. The difference is a charge, it is disclosed, it compounds, and the only question worth asking is what the higher-priced version is buying you.
4 min read · Updated 10 September 2026
Does Buying the Dip Improve Long-Term Outcomes?
Keeping some of each month's savings aside to buy when prices fall is one of the most common pieces of do-it-yourself strategy. We tested it across every fifteen-year stretch of the Indian market, with tax included — and then tested the exact opposite rule to check the answer.
6 min read · Updated 10 September 2026
Does Past Downside Protection Predict Future Protection?
A fund that fell less than the market in the last downturn is easy to find and easy to sell. Whether it will do the same next time is a completely different question — and answering it needs evidence almost nobody is ever shown.
4 min read · Updated 2 September 2026
Does SIP Date or Frequency Meaningfully Change the Outcome?
People put real thought into which date of the month their monthly investment should go out on. Across the whole record, the best date beat the worst by an amount that rounds to almost nothing — and the question of how often you invest has a more interesting answer.
3 min read · Updated 2 September 2026
Drawdown and Recovery Time, and How to Read Them
A drawdown figure is the one risk statistic expressed in the units of the actual experience. It is also quoted in two incompatible ways, and the one usually printed is the flattering one — it starts the clock at a moment nobody can identify while it is happening.
4 min read · Updated 10 September 2026
ETF or Index Fund? The Wrapper Matters Less Than the Transacting
Both hold the same index and are usually chosen on the same number, the expense ratio. That is the wrong comparison, because the two are bought and sold in completely different ways and the cost of transacting is where the difference actually lives — and it falls hardest at the moment you are least able to wait.
5 min read · Updated 10 September 2026
How Liquidity, Turnover and Trading Costs Affect Factor Strategies
Some funds pick shares by a fixed rule rather than by a manager's judgement, and they advertise how well that rule would have worked in the past. Those figures almost never include the cost of the buying and selling the rule requires — and on some strategies, that cost is bigger than the advantage being advertised.
6 min read · Updated 2 September 2026
Why Reinvesting Payouts Changes the Long-Run Result
A payout that is spent is a return you received once. A payout that is put back buys more of the thing that produces payouts, and does so again next time. Over long periods the difference between those two paths is not a detail — and it is the single reason the index figure quoted on the news understates what a shareholder actually got.
4 min read · Updated 10 September 2026
How Factor Investing Works
Instead of holding the market as it comes, hold more of the companies that share some measurable characteristic. The idea rests on decades of research and it has two competing explanations, only one of which implies the extra return should continue — which is the question to ask before buying one of these funds.
4 min read · Updated 10 September 2026
What an IDCW Payout Actually Is
A fund paying out is not a fund earning something extra. The payment comes out of the value you already owned, and the unit price falls by what was paid. Once that is clear, the choice between a payout option and a growth option stops being about income and becomes about tax and about when you want to sell.
4 min read · Updated 10 September 2026
How an Index Fund Actually Works
An index is a calculation. A fund is a portfolio. Getting the second to follow the first sounds trivial and is not, and the places where it is difficult are exactly where an index fund differs from another one tracking the same index.
5 min read · Updated 10 September 2026
How Investment Fees Reduce Wealth
A charge of one or two per cent a year sounds like rounding. It is not, and the reason it is not can be shown without assuming anything at all about what the investment returns — because the return cancels out of the arithmetic. What is left is a fraction of your money that the charge takes whatever happens.
4 min read · Updated 10 September 2026
How Low-Volatility Investing Works
Hold the shares that have moved about least, on the argument that they deliver most of the market's return with less of the turbulence. It is the most intuitively appealing of the factor strategies and it carries a hazard the others do not — its name describes what it selects for, and readers hear a promise about something else entirely.
4 min read · Updated 10 September 2026
How Much Diversification Is Enough
The benefit arrives fast and then stops. After a modest number of genuinely different holdings, adding more buys almost nothing while continuing to cost charges, complexity and attention — and past a certain point the complexity itself becomes the risk, because nobody maintains a portfolio they cannot see.
4 min read · Updated 10 September 2026
How Diversification Actually Works
It is described as not putting all your eggs in one basket, which gets the conclusion right and the mechanism wrong. Diversification does not work because you own many things. It works because the things you own do not all go wrong at the same time — and that distinction decides whether a portfolio is diversified or merely long.
4 min read · Updated 10 September 2026
Investing Abroad, and the Currency That Comes With It
Holding foreign shares gets you two things whether you wanted both or not: a claim on businesses elsewhere, and a position in a currency. They can move in opposite directions, and understanding which one you are actually trying to buy changes how much of it you should hold.
4 min read · Updated 10 September 2026
The Risk Numbers on a Fact Sheet, and What Each One Misses
Standard deviation, beta, maximum drawdown, downside deviation, tracking error. Five measurements that all get called risk, computed from the same price history, capturing different things and disagreeing with each other. A short guide to what each is actually counting — and to the two questions to ask before believing any of them.
5 min read · Updated 10 September 2026
How to See What Your Portfolio Actually Holds
A list of funds is not a portfolio. The portfolio is the combined list of companies underneath them, and it usually looks nothing like the fund list suggests — more concentrated, more repetitive, and quietly more so every year. This is how to work it out, with a spreadsheet and an afternoon.
4 min read · Updated 10 September 2026
What a Monte Carlo Simulation Does, and What It Assumes
Running a plan ten thousand times and reporting how often it worked is a genuine improvement on running it once. It is also the most confident-looking output in financial planning, and the confidence comes from the number of runs — which is the one thing about it that costs nothing and proves nothing.
4 min read · Updated 10 September 2026
NAV, Units and What Happens When You Buy or Sell
The mechanics are simple and are widely misunderstood in one specific way — a low NAV is routinely treated as cheap. It is not, and seeing why takes one paragraph. The rest of this page is the part that actually costs people money: which day's price you get, and what happens when you ask for your money back.
4 min read · Updated 10 September 2026
New Fund Offers and Closed-Ended Funds
A new fund is sold on the two things it cannot have — a record and a price you can judge. A closed-ended one adds a further constraint: you cannot leave when you want to. Both are structural facts rather than accusations, and both are enough to answer most of the question.
4 min read · Updated 10 September 2026
Nominal Return, Real Return and What Your Money Buys
Every return figure you are shown is in money. Money is not what you spend it on. The conversion between the two is a single subtraction most people can do in their head, and doing it changes which investments look adequate — including some that look perfectly safe.
4 min read · Updated 10 September 2026
Price Return and Total Return Are Two Different Indices
The index number quoted in the news leaves out dividends. The one a fund is measured against usually includes them. Comparing across the two makes an ordinary fund look impressive, and it is the most common unfair comparison in fund marketing — not because anyone is lying, but because the two indices carry almost the same name.
4 min read · Updated 10 September 2026
Why Published Inflation Is Not Your Inflation
The national figure is a weighted average of price changes across a basket somebody built to represent a typical household. You are not a typical household, and the further your spending sits from the average mix, the less the published number describes your experience — which is why it so often feels wrong.
4 min read · Updated 10 September 2026
What to Do When a Holding Is Underperforming
The instinct is to replace it, and the instinct is usually wrong — not because patience is a virtue but because one or two years of relative performance contains almost no information, and because the replacement is chosen by the same method that produced the disappointment. There is a better test, and it does not involve the return at all.
4 min read · Updated 10 September 2026
Risk and Volatility Are Not the Same Thing
Volatility is how much something moves about. Risk is not getting the money when you need it. The finance industry measures the first and calls it the second, because the first is easy to calculate — and the substitution quietly mislabels the safest-looking holdings as safe.
4 min read · Updated 10 September 2026
Rolling Returns Against Point-to-Point Returns
A point-to-point return is a single number produced by two dates somebody chose. A rolling return is what happened over every period of that length. Run both over the same Indian data and the headline figure turns out to be one draw from a distribution wide enough that two people doing the same thing for the same ten years ended up more than four times apart.
4 min read · Updated 10 September 2026
Setting a Return Expectation You Can Actually Plan Against
Every plan needs a number, and the number most people use is the wrong one in three separate ways at once — it is an average rather than what compounds, it describes shares rather than the portfolio, and it is stated as a point when the honest answer has a width. Fixing all three usually lowers it substantially, which is the useful part.
4 min read · Updated 10 September 2026
A SIP Does Not Remove Market Risk
Investing the same amount every month is genuinely useful, and what it is useful for is not what it is usually sold for. Run it across every period in the Indian record and the spread of outcomes is enormous — over five years the worst run lost money, and even over fifteen years two people doing precisely the same thing finished a long way apart.
5 min read · Updated 10 September 2026
A Lump Sum Has Arrived — Invest It or Stage It?
This is usually argued as though it were the same question as whether to invest monthly, and it is not. Most people never face it. Those who do are choosing between two things that differ less in expected outcome than in how it feels to be wrong, and that turns out to be the honest basis for deciding.
4 min read · Updated 10 September 2026
The Particular Risks of Thematic and Sector Funds
A fund built around one industry or one idea is a bet with three parts, and most buyers are only aware of one of them. The theme has to be right, it has to not already be in the price, and you have to still be holding when it pays. The structure also tends to put the fund in front of you at the worst possible moment.
5 min read · Updated 10 September 2026
Tracking Error and Tracking Difference Are Not the Same Thing
Two measurements with confusingly similar names, describing genuinely different things. One tells you how much an index fund cost you. The other tells you how bumpy the ride was relative to the index. Only the first bears on what you end up with, and it is the one less often quoted.
4 min read · Updated 10 September 2026
Why Long-Term Equity Returns Remain Uncertain
Holding shares for longer has narrowed the range of outcomes in India's recorded history. It has not removed the range — and the record we have is much shorter than the confident conclusions people draw from it.
4 min read · Updated 2 September 2026
What Mutual Fund Categories Are For
Fund categories exist so that two funds with the same label hold broadly the same kind of thing, which makes comparison possible and marketing harder. Knowing what the category system is for — and precisely how far its guarantee extends — is more useful than memorising the list.
4 min read · Updated 10 September 2026
Risk-Adjusted Return, and Why the Denominator Decides the Answer
The idea is sound and almost unarguable: a return earned with less turbulence is worth more than the same return earned with more. The trouble is that turning it into a ratio requires choosing what counts as risk — and that choice, not the fund, is usually what determines which fund comes out ahead.
4 min read · Updated 10 September 2026
What a SIP Is, and What It Is Not
A systematic investment plan is an instruction, not a product. Understanding that it is only a standing order into a fund clears up most of what people believe about it — including the belief that it is a kind of investment you can be sold, and that it does something to market risk.
4 min read · Updated 10 September 2026
What India VIX Actually Measures
It gets called the fear index, which is a good name for headlines and a poor one for understanding. It is a price, not a measurement — what people are currently paying for protection against the index moving, converted into an annual percentage. That distinction decides everything you can and cannot do with it.
5 min read · Updated 10 September 2026
What Alpha Means, and Why It Depends on the Benchmark
Alpha is meant to be the part of a return that the market cannot account for — the manager's contribution, isolated. It is a real and useful idea, and it has a property that is rarely stated plainly: it is defined relative to a benchmark somebody chose, so changing the benchmark changes the alpha without anything about the fund changing at all.
4 min read · Updated 10 September 2026
Why an Average Return Can Mislead You Badly
Add up the yearly returns, divide by the number of years, and you get a figure that is arithmetically correct and financially useless. On the Indian record it overstates what money actually did by enough to more than double the answer over a working lifetime — and the size of the error is not an accident of these particular years. It is a property of any series that moves about.
5 min read · Updated 10 September 2026
What a Fund Star Rating Can and Cannot Tell You
A star rating compresses a fund's history into a single symbol, which is exactly why it travels so well and why it carries so little. The ratings are not dishonest and they are not useless. They are backward-looking, relative, and recalculated as the market moves — three properties that decide what you may sensibly do with one.
5 min read · Updated 10 September 2026
Why Good Returns Do Not Make a Portfolio Safe
A strong number on a statement is a fact about a period that has ended. We asked what the trailing return looked like immediately before each large fall in the Indian record, and then ran the opposite test to keep ourselves honest. The result is not that a good run warns of trouble. It is something more awkward — the worst outcomes in the record came out of the portfolios whose past looked best.
5 min read · Updated 10 September 2026
Why Past Performance Is Not Enough to Choose a Fund
The warning is printed on everything and read by nobody, partly because it is never explained. This page explains it — what a track record can and cannot contain, the specific ways a published one is flattering, and the test that would settle whether past returns predict future ones. It also says plainly that we cannot run that test, and why the missing data is the interesting part.
6 min read · Updated 10 September 2026
Why Stock Markets Crash, and What the Record Actually Shows
Every crash gets an explanation afterwards and almost none of them are available in advance. What can be measured is the shape of the thing — how often falls arrive, how deep they go, how long they take to undo, and how much of an investing life is spent below a level the market has already reached. The last of those is the number nobody quotes.
6 min read · Updated 10 September 2026