Guides
ETF guides
Concepts you need when picking apart an ETF, one at a time — 35 pieces, readable in any order.
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Concepts you need when picking apart an ETF, one at a time — 35 pieces, readable in any order.
35 guides
Beginner
1201The index rose but my ETF didn't — finding the culprit with contributionAn ETF's move is the sum of its holdings' contributions. What contribution (%p) is, how it's computed, how to find today's hero and suspect, and why the biggest weight isn't always the culprit.02S&P 500 vs Nasdaq-100 — what differs and which to chooseHow do SPY and QQQ differ? Number of holdings, sector weights, tech concentration and volatility — plus the overlap you create by holding both.03What a 0.1% fee difference becomes in 20 years — the compounding of costsThe expense ratio looks tiny but compounds every year, eroding long-term returns. Why you should pick the lower-fee ETF when the index is the same — in numbers.04Don't take diversification on faith — reading an ETF's concentrationBuying an ETF can amount to buying a handful of stocks. How to use the concentration index (HHI) and top-10 weight to see how diversified a fund really is.
Intermediate
1501Your ETFs were secretly the same — the overlap trapDoes splitting across ETFs mean diversification? How holding S&P 500, Nasdaq-100 and a semiconductor ETF can multiply your real Apple/NVIDIA exposure — and how to check overlap.02How to pick a dividend ETF — high yield vs dividend growthChasing yield alone is risky. High-yield vs dividend-growth, the yield trap, expense ratios and dividend durability — what to actually check when picking a dividend ETF.03Not all semiconductor ETFs are equal — it's about what's insideTwo 'semiconductor ETFs' can perform very differently depending on NVIDIA weight, whether equipment makers are included, and domestic vs global mix. Why you must check holdings and concentration.04Why one KOSPI 200 ETF gets all the volume — the liquidity moatSeveral managers list a KOSPI 200 tracker, yet the trading piles into one. A look at the actual figures, why the gap forms, and whether the smaller ones are still fine to own.
Advanced
801Why you shouldn't hold leveraged ETFs for long — the math of decayWhy do 2x/3x leveraged ETFs lose money even when the index round-trips to flat? A number-first walk through volatility decay, why long holds are dangerous, and break-even math.02The appeal and traps of monthly covered-call income ETFsWhere does the monthly payout of a covered-call ETF come from? Option premiums, why upside is capped in rallies, and why distribution rate is not total return.03Three things to know before you buy an inverse ETFInverse ETFs rise when the index falls — yet being right about the direction does not guarantee a profit. Why that happens, and what these are actually for.04The ETF labelled 'synthetic' — what is actually differentA fund marked synthetic gets its index return through a swap instead of owning the shares. What changes, and what risk that adds.
Beginner
1201The index rose but my ETF didn't — finding the culprit with contributionAn ETF's move is the sum of its holdings' contributions. What contribution (%p) is, how it's computed, how to find today's hero and suspect, and why the biggest weight isn't always the culprit.02S&P 500 vs Nasdaq-100 — what differs and which to chooseHow do SPY and QQQ differ? Number of holdings, sector weights, tech concentration and volatility — plus the overlap you create by holding both.03What a 0.1% fee difference becomes in 20 years — the compounding of costsThe expense ratio looks tiny but compounds every year, eroding long-term returns. Why you should pick the lower-fee ETF when the index is the same — in numbers.04Don't take diversification on faith — reading an ETF's concentrationBuying an ETF can amount to buying a handful of stocks. How to use the concentration index (HHI) and top-10 weight to see how diversified a fund really is.05Two numbers to check before the expense ratioFees are easy to compare, so they get looked at first. Check net assets and turnover before them, or you can lose more than the fee you saved.06Why the name is not the fund — read the holdings insteadTwo funds can carry the same theme in their names and hold very different companies. Why that gap opens, and what to check.07What happens if your ETF closesFunds do close. What the process looks like, what happens to your money, and how to see it coming.08One fund for everything — who asset-allocation ETFs are forFunds that pre-mix stocks and bonds, and target-date funds that shift over time — how they work and what to check.09Why your ETF looks like it beat the index — total return vs price returnThe index you see in the news is usually price return — dividends excluded. Here is the mismatch that creates against a dividend-collecting ETF, and what you should actually compare.10Which ETFs a Korean pension account can and cannot buyKorean retirement accounts restrict what you may hold. Leveraged and inverse limits, the risk-asset cap, and why foreign-listed ETFs are off the menu.11Is a P/B under 1 actually cheap? What book value does and doesn't tell youWhat price-to-book measures, why so many Korean listings trade under 1x, what book value leaves out, and how to read P/B at the ETF level.12P/E and EPS — pricing a stock in years of earningsWhat P/E and EPS mean, trailing versus forward, the traps that make a P/E look low, and how to read index- and ETF-level multiples.
Intermediate
1501Your ETFs were secretly the same — the overlap trapDoes splitting across ETFs mean diversification? How holding S&P 500, Nasdaq-100 and a semiconductor ETF can multiply your real Apple/NVIDIA exposure — and how to check overlap.02How to pick a dividend ETF — high yield vs dividend growthChasing yield alone is risky. High-yield vs dividend-growth, the yield trap, expense ratios and dividend durability — what to actually check when picking a dividend ETF.03Not all semiconductor ETFs are equal — it's about what's insideTwo 'semiconductor ETFs' can perform very differently depending on NVIDIA weight, whether equipment makers are included, and domestic vs global mix. Why you must check holdings and concentration.04Why one KOSPI 200 ETF gets all the volume — the liquidity moatSeveral managers list a KOSPI 200 tracker, yet the trading piles into one. A look at the actual figures, why the gap forms, and whether the smaller ones are still fine to own.05The (H) on a fund's name — when hedging helps and when it costsAn (H) means the fund strips out currency moves. How that changes returns, and what it costs to do.06What actually happens inside an ETF when it rebalancesWhen the index changes, the fund trades. How additions and deletions get decided, and how that reaches your return.07Premium and discount — the price you pay may not be the value you getAn ETF's market price and its net asset value can diverge. Why that gap opens, when it widens, and what to watch so it does not cost you.08Why bond ETFs fall when rates rise — reading durationWhy the safe asset you bought dropped hard, explained through duration — and how to choose between maturities.09When to place an ETF order — spreads and market makersThe same fund fills differently depending on when you trade. Why the open and the close are the worst moments, and the risk in market orders.10Why thematic ETFs always arrive late — the structural bias in launch timingSectors and themes are not the same product. Why thematic funds tend to list near the peak of a story, and what to check if you want one anyway.11Same 500 stocks, different outcome — equal weight vs cap weightIdentical constituents, different weighting, different product. What cap weighting and equal weighting each do automatically, and the markets where they diverge.12Bond ETFs that actually mature — how target-maturity funds differOrdinary bond ETFs never mature. How target-maturity funds change that, and what differs between holding to the end and selling early.13ROE — a cheap company and a good company are different thingsWhat return on equity measures, how to decompose it, how to spot ROE inflated by leverage, and how the P/B = P/E × ROE identity exposes what is really wrong with a cheap stock.14Market cap and free float — who decides the weights in your ETFHow market cap is computed, why indexes weight by free float instead, how reviews and additions shift weights, and why your fund's weights change without you doing anything.15Reading a fund's character from P/B, P/E and ROEHow per-stock ratios aggregate to fund level, how to tell value, growth and quality apart from the numbers, what the numbers cannot answer, and the order to check things in.
Advanced
801Why you shouldn't hold leveraged ETFs for long — the math of decayWhy do 2x/3x leveraged ETFs lose money even when the index round-trips to flat? A number-first walk through volatility decay, why long holds are dangerous, and break-even math.02The appeal and traps of monthly covered-call income ETFsWhere does the monthly payout of a covered-call ETF come from? Option premiums, why upside is capped in rallies, and why distribution rate is not total return.03Three things to know before you buy an inverse ETFInverse ETFs rise when the index falls — yet being right about the direction does not guarantee a profit. Why that happens, and what these are actually for.04The ETF labelled 'synthetic' — what is actually differentA fund marked synthetic gets its index return through a swap instead of owning the shares. What changes, and what risk that adds.05The index rose 10%, the fund 9.4% — where tracking difference comes fromWhy a fund never quite matches its index — fees, rebalancing costs, dividend handling and sampling, taken one at a time.06Monthly distributions — where does that cash actually come from?A monthly payout is not always money the fund earned. How to tell the sources apart, and what to check when the yield looks high.07Oil rose, the oil ETF didn't — the cost of rolling futuresMost commodity funds hold futures, not the commodity. Why replacing expiring contracts erodes long-run returns.08Why smart beta underdelivers its backtestValue, momentum, quality and low-volatility funds show clear excess returns in historical data. Here is what sits between those numbers and live performance.