A beginner-friendly guide to why the market swings so wildly, day after day
The KOSPI surged 6.24% yesterday (July 15), then reversed course today (July 16), tumbling 6.37% to close at 6,820.60. The index has been swinging wildly for days on end, and today we break down exactly what’s driving this dizzying back-and-forth in plain terms.
What Happened Today
The KOSPI closed down 463.81 points (6.37%) at 6,820.60. SK hynix, which had led yesterday’s double-digit rally, reversed hard and plunged 11.53%, dragging the index lower. As prices fell too fast during the session, a “sell-side sidecar” — a circuit-breaker-like safeguard — was triggered. A sidecar automatically halts program trading for five minutes when futures prices move too sharply in a short period, preventing the market from overshooting. The opposite version, a “buy-side sidecar,” kicked in yesterday when prices spiked upward.
Why All the Turbulence? Blame Single-Stock Leveraged ETFs
Market analysts point to “single-stock leveraged ETFs” as the main driver behind the recent surge in volatility. In simple terms, these are products that track a single stock’s (like SK hynix) daily price move at 2x — meaning they’re designed to rise twice as fast, and fall twice as fast, as the underlying stock. As money has poured into these products, even a small wobble in the underlying stock triggers an outsized wave of related trading, amplifying moves across the entire index. Goldman Sachs itself recently pointed to this leveraged-ETF-driven flow imbalance as a key culprit behind the KOSPI’s sharp declines.
The VKOSPI, Korea’s version of the “fear index” that tracks KOSPI 200 volatility, spiked to an all-time high of 97.99 since records began. A reading above 50 is typically considered “extreme fear” territory — meaning today’s level is nearly double that threshold. Sidecars have now been triggered 34 times so far this year, more than 13 times the historical annual average of 2.5, and already surpassing the 2008 financial crisis’s full-year total of 26 — in just over six months.
Retail Investors’ Contrarian Bets: Sell When It Rises, Buy When It Falls
What’s striking is how retail investors have responded. When the index surged 6.24% yesterday, the top net-bought product among individual investors was an “inverse” ETF — a product that profits when the index falls. In other words, investors were betting on a pullback even as the market rallied. Today, as the index tumbled 6.37%, the top net-bought product flipped to an SK hynix leveraged ETF — the exact opposite bet, wagering on a rebound tomorrow.
Still, retail investors as a whole were net sellers today, offloading roughly 5 trillion won (likely a mix of profit-taking and stop-losses), while foreign and institutional investors absorbed that supply and helped defend the 6,800 level. The government moved quickly too: President Lee Jae-myung ordered officials to swiftly draw up supplementary measures for leveraged ETFs, and news of the directive appeared to calm investor sentiment somewhat.
Other Headlines Moving the Market Today
- EcoPro BM’s rights offering hits a snag: EcoPro BM’s planned 1.2 trillion won rights offering was thrown off schedule after the Financial Supervisory Service demanded corrections to its securities registration statement.
- SK hynix earnings forecasts cut again: Analysts trimmed their earnings estimates for SK hynix once more. Some, however, argue the cut is “already largely priced in,” framing the pullback as a buying opportunity instead.
Investor Takeaways and Expert Views
⚠️ Things Investors Should Watch
- Leveraged products cut both ways: They can rise twice as fast, but they can also fall twice as fast. In a market flipping direction daily like this one, losses can snowball within a day or two.
- Don’t chase short-term momentum: Simple trend-following logic — “it rose yesterday so it’ll rise today,” or “it fell yesterday so it’ll bounce today” — may not hold up in this kind of extreme volatility.
- Frequent sidecars and circuit breakers are a warning sign: Triggering 34 times this year alone signals just how unstable the market currently is. A more conservative approach to position sizing is warranted.
- Wait to see policy measures actually implemented: The government’s leveraged ETF measures are still just a directive at this stage. It’s safer to wait for concrete details and an implementation timeline before factoring them into investment decisions.
📌 What Experts Are Saying
- Lee Jae-won, Yuanta Securities analyst: Noted that recent market moves stem from leveraged-ETF-driven volatility and a lack of consistent buyers, pushing valuations below financial-crisis-era levels — even though semiconductor supply and demand, and corporate earnings trajectories, haven’t changed enough to justify the sell-off. He advised continuing to trim leverage exposure during periods of heightened volatility.
- Goldman Sachs: Identified single-stock leveraged ETF-driven flow imbalances as the key factor behind the KOSPI’s recent sharp declines.
In short, the current turbulence looks less like a reaction to a sudden shift in corporate earnings or economic fundamentals, and more like a structural issue where money flooding into leveraged products is amplifying volatility on its own. Rather than reacting to each day’s swing, it’s worth watching how the government’s leveraged ETF measures actually take shape, and whether the underlying direction of the semiconductor cycle and corporate earnings holds steady.