Pitfield St Derivatives data archive

SPY

Snapshot 2026-09-07 at 4:20 PM ET spot 589.91 pipeline v0.1.0

x log-moneyness ln(K/F) y implied volatility z maturity, √T spacing Drag to rotate, scroll to zoom, arrow keys when focused

Implied volatility

ATM implied, 30 day15.18%
ATM implied, 60 day15.19%
ATM implied, 90 day15.20%
Term slope, 90 − 300.02%
Term shapecontango
IV rank, 252 day64.3%
IV percentile55.4%
25Δ risk reversal0.88%
25Δ butterfly0.05%
ATM skew, ∂σ/∂k-0.1576

IV rank and percentile are computed against this ticker's own trailing history in the archive, 139 days so far, so read them as provisional until the window fills.

The smile, expiry by expiry

Points are market implied volatilities inverted from mid quotes; the line is the calibrated SVI fit. Each expiry is drawn only across the strikes that had a two-sided quote with open interest.

Term structure

Realized volatility

Five estimators, annualised on 252 trading days. They disagree by construction: the range estimators use only intraday prices and are blind to the overnight gap, which is exactly what Yang–Zhang adds back.

Estimator 5d10d21d63d252d
Close-to-close 17.5413.5614.0715.1315.29
Parkinson 11.6310.9612.2212.7913.05
Garman–Klass 12.1311.6911.5012.3912.63
Rogers–Satchell 13.0012.6411.4512.5012.49
Yang–Zhang 14.8814.5913.6614.1614.53
Parkinson ÷ close-to-close 0.6630.8080.8690.8450.854

Gamma exposure

Total gamma exposure−$6.68m
Gamma flip strike399.89
Max-gamma strike600.00
Max open-interest strike600.00
Put/call ratio, volume1.002
Put/call ratio, open interest1.000

Fit quality, by expiry

Days Forward Rate Parity R² RMSE (vol pts) Used Dropped min g(k) Butterfly
7 590.25 4.351% 1.000000 0.165 13 68 0.73372 pass
14 590.60 4.351% 1.000000 0.185 20 61 0.71349 pass
21 590.94 4.351% 1.000000 0.125 24 57 0.73267 pass
28 591.29 4.351% 1.000000 0.109 29 52 0.70858 pass
35 591.63 4.311% 1.000000 0.064 33 48 0.71281 pass
49 592.33 4.376% 1.000000 0.104 40 41 0.69637 pass
63 593.02 4.299% 1.000000 0.119 46 35 0.67632 pass
91 594.41 4.357% 1.000000 0.052 58 23 0.59136 pass
119 595.81 4.359% 1.000000 0.084 67 14 0.57579 pass
154 597.54 4.351% 1.000000 0.095 76 5 0.56646 pass
182 598.95 4.346% 1.000000 0.078 80 1 0.57094 pass
273 603.52 4.353% 1.000000 0.056 81 0 0.60080 pass
365 608.18 4.349% 1.000000 0.049 78 3 0.64612 pass

69.4% of the chain was excluded from the fits, zero-bid, crossed, no open interest, beyond the moneyness cut, or not invertible. The exclusion rate is published because it is part of the result: a surface fitted to a third of a chain is a different object from one fitted to all of it. Full history on the quality page.