The three observed quantities
Sector relative strength = how far a sector's return has beaten the broad market's over the trailing quarter (a price proxy for crowding)
Market breadth = how many stocks participate in the rally (equal-weight index underperforming cap-weight = narrowing breadth)
% above 200-day MA = how far price sits above its own 200-day moving average (the standard BIAS technical indicator)
How the light is decided
🔴 Red: hottest sector's relative strength enters the top 5% of 10 years (≥95) AND market breadth narrows into the top 10% (≥90) — both must hold
🟡 Amber: relative strength ≥95 but breadth only to ≥60; or either relative strength or 200-day bias enters the top 1% (≥99)
🟢 Green: everything else
Once red has fired, it doesn't snap straight back to green: it must exit the top 20% (relative strength) or the top 60% (breadth) before returning to green, resting on amber in between (anti-flicker)
Any missing data shows “No data” — it never defaults to green