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The only risk-management rule that matters

Forget complex position-sizing models. Here's the one rule that survives every market condition, and the math that makes it work.

Almost everything written about risk management is overcomplicated. You don't need Kelly criterion calculators, Sharpe-optimized portfolios, or a 12-step checklist.

You need one rule:

Never risk more than 1% of your account on a single trade.

That's it. Everything else is decoration.

What "risk 1%" actually means

It does not mean buying €1,000 worth of BTC when your account is €100,000. That's position size, not risk.

Risk = (entry price − stop loss) × position size

Example:

That position sizes itself based on where the stop is, not on how confident you feel.

Why this rule survives

If you risk 1% per trade:

If you risk 5% per trade:

The asymmetry is brutal. Big losses require exponentially bigger gains to recover from. A 50% loss requires a 100% gain to break even. A 75% loss requires a 300% gain.

This is why almost every trader who blows up does so the same way: they were doing fine, then took 2-3 oversized positions, lost on them, and discovered they couldn't dig out. The 1% rule is the wall between "down a bit" and "account destroyed".

The math of streaks

Even with a 60% win rate, the probability of 5 losses in a row is non-trivial. Let me prove it:

Roughly 1 in 100 sequences of 5 trades. Over a year of 200 trades, expect this to happen 2 times.

With a 50% win rate (very common for beginners), 5 losses in a row happen 3% of the time, or about 6 times in 200 trades.

If your 5-loss streak takes you down 25% (5 trades × 5% risk each), you're now in a -33% recovery hole. Multiple streaks compound.

If your 5-loss streak takes you down 5% (1% risk), you're barely scratched. Same trader, same skill, completely different outcome.

"But 1% is so small, I'll never get rich"

Here's where most beginners trip.

Risking 1% per trade does not mean you make 1% per trade. With a 1:2 reward-to-risk ratio, your average winner makes 2% of account. With a 50% win rate, your expected return per trade is:

(0.5 × 2%) − (0.5 × 1%) = 0.5% per trade

Over 200 trades a year (1 trade per trading day), that's a 100% annual return before compounding. Compounded, more.

That's the math the impatient beginner doesn't see. They want 5x in 6 months, so they risk 5% per trade. Most blow up. The 1%-trader compounds steady and eats their lunch over 3 years.

What this looks like operationally

  1. Calculate your account value at the start of each week. Lock in "1% = €X".
  2. For every trade you consider:
    • Where is the stop loss going to be? (Decided before entry, based on chart structure)
    • What's the distance from entry to stop?
    • Position size = €X / distance
  3. If the math gives you a position size larger than your account allows (e.g., 5x leverage), you have two choices: skip the trade, or move the stop closer (which usually means trading a smaller timeframe).
  4. Never skip step 1-3 because "this one looks easy." That's the trade that kills you.

The exception that proves the rule

There's exactly one valid reason to risk more than 1%:

The opportunity is so asymmetric and so rare that even if you lose, the long-term expected value is positive.

These are real, but rare, 2-4 times per year at most. Examples: a clear macro setup, a market crash where everything sane is on sale, a clear breakout from a 6-month consolidation. If you find yourself thinking "this is the one" more than 5 times a year, you don't have an exception, you have FOMO with a justification.

What to do this week

  1. Calculate your 1% number. Write it on a sticky note next to your monitor.
  2. For your next 20 trades, position-size strictly off the 1% rule, even if it feels too small.
  3. After 20 trades, look at your equity curve. The smoothness alone will convince you.

Then never risk more than 1% again.

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The only risk-management rule that matters · AstroPark