← Back to Blog · 2026-10-08 · 8 min read · Strategy Case Study

Picture this: it's the first half of 2021, and you're watching rebar futures on the Shanghai Futures Exchange go almost vertical. Steel mills are talking production cuts, Tangshan is under environmental restrictions, and every pullback gets bought within two sessions. You either rode it, chased it, or — like most traders — watched it happen while your system kept telling you to wait for confirmation that never felt comfortable.

Then, roughly in mid-May, the market rolled over hard after Beijing stepped up rhetoric about commodity price inflation. Traders who bought the top got destroyed. Traders who shorted the crash too early got squeezed. And traders running a disciplined trend-following process? They had a very instructive year — one worth dissecting, because rebar remains one of the most liquid and tradable contracts in Chinese commodity futures today.

Let's run the tape.

What Actually Drove the 2021 Rebar Rally

The 2021 move wasn't a quiet grind. It was a policy-driven bull market layered on top of a genuine demand recovery, and understanding that mix matters for anyone who wants to trade rebar or iron ore going forward.

• Supply-side compression. China's carbon-neutrality pledges and crude steel output reduction targets created a credible narrative that supply would stay tight. Tangshan-area environmental restrictions limited production at major mills.
• Strong construction demand. Property and infrastructure activity in early 2021 kept physical demand healthy, so the supply story wasn't fighting the demand side — it was compounding it.
• Speculative momentum. As prices climbed, open interest and retail participation surged, which is typical of Chinese commodity futures in a strong trend. Momentum fed momentum.

Rebar futures pushed up through the spring and reached levels well above anything seen in the previous several years — the main contract traded up around the 6,000 yuan-per-ton area near the peak, roughly 40% or more above where the year started. Then came the turn: in mid-May, senior Chinese officials publicly signaled concern about commodity prices, and the market's response was swift and brutal. Rebar dropped hard within days. That single episode — a parabolic run followed by a policy-triggered reversal — is the entire case study in miniature.

The second half of the year added another chapter: thermal coal on the Zhengzhou and Dalian exchanges went on an even more extreme rally into the autumn before NDRC intervention crushed it in October. If 2021 taught Chinese commodity futures traders anything, it's that policy risk is a first-class market factor, not a tail event.

Know Your Instrument: Rebar Contract Specs on the SHFE

Before we talk strategy, let's ground this in the actual contract. Sloppy assumptions about sizing are how trend-followers blow up before the trend even matters.

Two practical notes. First, the night session matters for trend-followers: global risk sentiment and overnight news get priced in before the day session opens, and gaps through your stop are a real possibility. Second, exchanges in China actively adjust margins and position limits when volatility spikes — exactly the kind of periods a trend-follower lives for. Build that into your risk model rather than being surprised by it.

The System: A Deliberately Simple Trend-Following Rule Set

For this dissection, let's use a classic, transparent framework — the kind you could code in an afternoon. No curve-fitting, no magic indicators.

Entry

• Go long when the daily close breaks above the highest high of the previous 20 trading sessions (a Donchian-style channel breakout).
• Go short on the mirror-image breakdown below the 20-day low.
• Optional filter: only take longs if price is above a 50-day moving average. This keeps you out of breakdown signals inside a raging uptrend that then reverse immediately.

Exits and Stops

• Initial stop: 2× ATR(14) below entry. On rebar in 2021, daily ATR was expanding dramatically through the spring — by the peak, 2× ATR might have meant a stop several hundred yuan per ton away, i.e., thousands of CNY per lot.
• Trailing exit: exit longs on a close below the lowest low of the last 10 sessions, or a 3× ATR trailing stop, whichever gets hit first.
• Re-entry allowed after a new 20-day high forms again. This is critical — the re-entry rule is what separates trend-followers from one-shot traders.

Position Sizing

• Risk a fixed fraction per trade — say 1% of account equity — calculated as (entry minus stop) × 10 CNY per lot, then divide to get lot count.
• Cap total portfolio heat. If you're also trading iron ore, hot-rolled coil, or thermal coal, remember these markets are highly correlated through the steel and energy complex. Three simultaneous breakouts in correlated contracts is not three independent trades.

Nothing here is exotic. That's the point. The question is not whether the rules are clever — it's how they would have behaved inside 2021's specific price structure.

What the System Would Have Caught

The spring rally was almost a laboratory-perfect trend-following environment.

• Multiple clean long entries. As rebar climbed through February, March, and April, the 20-day breakout fired repeatedly. The optional 50-day MA filter would have kept you long the whole way. Each pullback that held above the 10-day low let the trailing exit breathe.
• Pyramiding-friendly structure. The rally came in impulses — steady advances followed by shallow consolidations — which is exactly the geometry that lets a breakout system add on strength rather than buy exhaustion. A trader sizing each new breakout at 1% risk could have built a meaningful position while keeping worst-case loss defined.
• The volatility payoff. Trend-following earns its keep in the fat right tail. The bulk of rebar's 2021 gains came in a handful of explosive weekly moves. A system that stayed in through the noise captured those; a system that took profits at +2R every time did not.

By late April into early May, a patient trend-follower would have been sitting on the largest open profit of the year with a trailing stop hundreds of yuan per ton below the market. That's the dream scenario the whole approach is built around.

What It Would Have Missed — and What It Would Have Bled

Now the honest part. Trend-following is a paying-for-insurance strategy, and 2021 sent the premiums due.

The May top was a giver-back, not an exit signal

When the policy-driven reversal hit in mid-May, rebar didn't politely close below a 10-day low on day one. It gapped and plunged. A trailing stop that wide — appropriate for the trend's volatility — surrendered a substantial chunk of open profit before getting filled. This is structural, not a flaw you can optimize away: tighten the trail and you get shaken out during the trend; widen it and you give back a slice of the peak. Every trend-follower chooses their poison.

The whipsaw zone

After the May crash, the market spent weeks in violent two-way trade — sharp bounces, sharp selloffs, headlines whipsawing sentiment in both directions. A 20-day breakout system in that regime produces a string of small losses: long breakout, reversed; short breakdown, squeezed. Five, six, seven consecutive small losses is entirely realistic. Traders who have never sat through a losing streak in Chinese commodity futures tend to abandon the system precisely when it's behaving normally.

The second leg required the re-entry rule

Later in the year, steel complex markets staged renewed strength before the broader autumn commodity surge (with thermal coal as the extreme case) and subsequent policy intervention. A trader who rage-quit after the May whipsaws missed the re-entries. The mechanical re-entry rule isn't a nicety — it's the difference between catching the second leg and watching it from the sidelines with your pride.

What no breakout system catches

The exact top. The exact bottom of the crash. The intraday spikes around policy headlines. If your backtest shows a system nailing those, you've over-fit, not discovered an edge. A trend-follower's job is to be present for the middle 60% of a move, not the endpoints.

The lesson isn't that trend-following failed in 2021. It's that trend-following did its job — caught a large move, gave back a defined slice, absorbed a losing streak — and the trader's real job was to not interfere.

Three Lessons for Trading Chinese Commodity Futures Today

• Respect policy risk as a stop-loss event. Chinese regulators can and do move markets with statements, not just actions. Position sizing that assumes only gradual price movement is mispriced risk. In 2021, both rebar (May) and thermal coal (October) showed how fast intervention can reprice a market.
• Size for the gap, not the tick. With night sessions and headline-driven moves, your true risk on a rebar position is beyond your stop, not at it. Sizing at 1% risk with a mental haircut for slippage is the conservative read.
• Treat the steel complex as one trade. Rebar, hot-rolled coil, iron ore, and coke often move together. Diversification across correlated Chinese commodity futures is thinner than it looks on a spreadsheet.

How to Apply This Without Paying Tuition in Live Markets

Reading about the 2021 rebar run is cheap; discovering that your actual temperament can't sit through seven consecutive whipsaw losses is expensive. That gap between theory and behavior is exactly what a structured evaluation process is for.

Take the rule set above — 20-day breakout, ATR stops, 1% risk — and write it down precisely enough that a computer could execute it. Then run it against real Chinese commodity futures data, including the ugly stretches. Does your trailing stop width match your stomach? Does your lot sizing survive a gap through the night session? Would you have re-entered in June after giving back a third of your May profits?

If you want to test a system like this under realistic conditions, you can run it on a real-data China futures evaluation at XS Select, with evaluations starting from $29. It's a straightforward way to find out whether your trend-following process — not just your backtest — holds up, before real capital is on the line.

The Bottom Line

The 2021 rebar bull run rewarded the oldest virtues in trading: enter on evidence, trail with discipline, size so that no single reversal can take you out of the game, and re-enter without ego after being stopped. It punished everything else — top-picking, averaging down, and abandoning systems mid-drawdown.

Trend-following in Chinese commodity futures will never feel comfortable. That's not a bug. The discomfort is the price of admission, and 2021 was the year that priced it clearly.