What it means
Circuit breakers are pre-set thresholds (typically -7%, -13%, -20% on the S&P 500) that halt trading for a fixed period when triggered. They exist to prevent flash crashes from cascading into algorithmic feedback loops.
Why it matters
March 2020 hit Level 1 circuit breakers four times in two weeks. The mechanism worked - it gave markets time to absorb panic without runaway selling. But it can't fix anything fundamental.
How to use it
Know the levels. Don't try to trade through halts; the resumption usually comes with significant gaps. Adjust position sizes during high-volatility regimes.
Take it further
Want a worked example or a deeper dive? Ask Rocky how this concept applies to your specific watchlist or trade idea.
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