SPY· SPDR S&P 500 ETF Trust
Dark pool · off-exchange short volume
Short ratio (latest)
43.0%
20-day average
58.1%
Off-exchange share (20d)
34%
Darkpool density
big day, short ratio above trendbelow trendbubble size = how unusual ($vol z-score)
Last ~6 months. Bubbles mark days of unusually large off-exchange dollar volume (≥1.5σ vs the trailing 60 days). Daily resolution — not print-level data.
Darkpool levels ±15% of spot, since 2018-10-01
779.58
77.5B
764.29
221B
749.00
418B
733.72
339B
718.43
72.1B
703.15
120B
687.86
587B
672.58
788B
657.29
611B
Historical off-exchange $ volume at price: each day's volume spread across that day's range, summed over the full FINRA history. Heavy shelves often act as support/resistance magnets. Amber row = spot's bin.
Off-exchange short-volume ratio
short ratio (20d, right) daily off-exchange share (left)
FINRA daily TRF data, last 2 years. A persistently HIGH short ratio is mostly passive market-maker liquidity provision (commonly read as accumulation pressure) — not naively bearish.