Round numbers on US30: magnet or folklore?
Posted: Sun Oct 04, 2026 10:46 am
Ask ten scalpers whether round numbers on the Dow matter and you'll get ten confident answers. I wanted to see what my own data said, because I have a habit of drawing lines at every thousand and every five hundred points and I've never checked whether those lines earn their place.
What I measured: from January to September, every time US30 came within 20 points of a 500-point level during 14:30 to 18:00 London, I recorded whether price touched the level, whether it reversed by at least 50 points within 15 minutes, or whether it went through by at least 50 points.
What I found, across 64 approaches:
Price touched the level in 51 of them. That's 80%, which sounds like a magnet, but a 20-point approach is close enough that touching isn't surprising.
After touching, price reversed by 50 points in 24 cases and continued by 50 points in 19. The rest were indecisive.
At thousand-point levels specifically the reversal rate was a bit higher, but the sample is only 18.
So is it a magnet? Mildly, perhaps. Is it a reliable reversal point? Not really. It's slightly better than a coin flip, which isn't enough to trade on its own after costs.
What I now do is use round numbers only as a filter. I don't take a long right underneath a big round number, and I don't fade one without something else supporting it.
What I measured: from January to September, every time US30 came within 20 points of a 500-point level during 14:30 to 18:00 London, I recorded whether price touched the level, whether it reversed by at least 50 points within 15 minutes, or whether it went through by at least 50 points.
What I found, across 64 approaches:
Price touched the level in 51 of them. That's 80%, which sounds like a magnet, but a 20-point approach is close enough that touching isn't surprising.
After touching, price reversed by 50 points in 24 cases and continued by 50 points in 19. The rest were indecisive.
At thousand-point levels specifically the reversal rate was a bit higher, but the sample is only 18.
So is it a magnet? Mildly, perhaps. Is it a reliable reversal point? Not really. It's slightly better than a coin flip, which isn't enough to trade on its own after costs.
What I now do is use round numbers only as a filter. I don't take a long right underneath a big round number, and I don't fade one without something else supporting it.