Surge days count stocks that gain 20%+ in five trading sessions. Plunge days count those that lose 20%+ in five sessions. This burst-momentum measure captures the most explosive institutional moves in the market.
The 4%+ single-day count captures broad institutional participation. The 20%-in-5-days count goes further: it identifies the names experiencing burst momentum — the kind of explosive, multi-day gains that mark the most aggressive accumulation phases in the market.
A surge day counts every stock that has gained 20%+ over the prior five trading sessions (one calendar week). A plunge day counts those that have fallen 20%+ over the same window. These counts are narrower than the 4%+ daily figures — on a typical day, perhaps 30–80 stocks are surging — but their diagnostic value is high precisely because of that rarity.
When the surge count expands significantly — say, 80 or 100+ stocks gaining 20%+ in a week — it signals that institutional buyers are deploying aggressively into growth names. This is the kind of internal environment where breakout setups work best: the tape is rewarding offensive positioning rather than punishing it.
Historically, a persistent surge count expansion (several weeks of elevated readings) has correlated with early-to-mid trend phases, before the index becomes crowded and starts drawing profit-takers. Catching the first few weeks of a surge expansion is one of the highest-edge entry points for momentum traders.
Elevated plunge readings — many stocks losing 20%+ in a week — indicate that distribution is broad and deep. These aren't just index-level moves; individual names are being sold aggressively across the universe. A sustained high plunge count is one of the clearest signals that the environment does not favour new long positions.
The plunge count can spike sharply during market bottoming processes as the final exhaustion selling hits. A plunge spike followed by a rapid surge recovery is a classic reversal signature — the breadth equivalent of a capitulation candle on the index.
The surge/plunge columns on the WideRadar Breadth heatmap complement the other columns rather than replace them. The hierarchy to read is:
All three confirming the same direction gives you a high-conviction read. Divergence between them — e.g. a strong 4%+ day alongside a declining surge count — is worth noting but not necessarily acting on until the pattern resolves.
Sources & References
Track market breadth, sector rotation, and leadership scores across 12,000+ US stocks — start your 14-day free trial, full access from day one.
Try it free →Cancel anytime