{"schemaVersion":1,"asset":"BTC","reportDate":"2026-09-27","timestamps":{"currentSnapshotAt":"2026-09-27T19:05:00+00:00","previousSnapshotAt":"2026-09-26T19:05:00+00:00","generatedAt":"2026-09-27T19:05:44+00:00"},"comparison":{"status":"available","note":null},"provenance":{"reportArtifact":"published daily report","sourceReport":"BTC","sourceReportHref":"/reports/2026-09-27","source":"Derivasys proprietary historical SVI surface and canonical BTC index databases","comparison":"Nearest successful surface snapshots approximately 24 hours apart","rrConvention":"25-delta call IV minus 25-delta put IV","bfConvention":"Average 25-delta wing IV minus ATM forward IV","fixedTenors":"Fixed-tenor measures are published only when listed expiries bracket the target at both comparison snapshots. Targets outside either observable range are suppressed, not extrapolated; headline rankings use only supported tenors.","realisedVolatility":"Annualised root-mean-square of one-minute canonical BTC-USD index log returns using a 365-day basis; all windows end at the current snapshot."},"tenors":[{"tenor":"1W","targetExpiry":1791140700082,"availability":"available","unavailableReason":null,"atmIv":{"current":32.76,"previous":30.7,"change":2.06,"percentChange":6.71},"rr25":{"current":-0.62,"previous":-1.29,"change":0.67,"percentChange":51.94},"bf25":{"current":1.8,"previous":1.65,"change":0.15,"percentChange":9.09}},{"tenor":"2W","targetExpiry":1791745500082,"availability":"available","unavailableReason":null,"atmIv":{"current":32.99,"previous":31.93,"change":1.06,"percentChange":3.32},"rr25":{"current":-0.81,"previous":-1.16,"change":0.35,"percentChange":30.17},"bf25":{"current":1.65,"previous":1.64,"change":0.01,"percentChange":0.61}},{"tenor":"1M","targetExpiry":1793127900082,"availability":"available","unavailableReason":null,"atmIv":{"current":34.05,"previous":33.74,"change":0.31,"percentChange":0.92},"rr25":{"current":-0.71,"previous":-1.07,"change":0.36,"percentChange":33.64},"bf25":{"current":1.67,"previous":1.71,"change":-0.04,"percentChange":-2.34}},{"tenor":"3M","targetExpiry":1798398300082,"availability":"available","unavailableReason":null,"atmIv":{"current":36.85,"previous":37.1,"change":-0.25,"percentChange":-0.67},"rr25":{"current":-1.07,"previous":-0.99,"change":-0.08,"percentChange":-8.08},"bf25":{"current":2.01,"previous":2.09,"change":-0.08,"percentChange":-3.83}},{"tenor":"6M","targetExpiry":1806260700082,"availability":"available","unavailableReason":null,"atmIv":{"current":37.81,"previous":37.95,"change":-0.14,"percentChange":-0.37},"rr25":{"current":-0.72,"previous":-0.58,"change":-0.14,"percentChange":-24.14},"bf25":{"current":2.24,"previous":2.32,"change":-0.08,"percentChange":-3.45}},{"tenor":"9M","targetExpiry":1814123100082,"availability":"available","unavailableReason":null,"atmIv":{"current":38.52,"previous":38.76,"change":-0.24,"percentChange":-0.62},"rr25":{"current":-0.39,"previous":-0.19,"change":-0.2,"percentChange":-105.26},"bf25":{"current":2.37,"previous":2.45,"change":-0.08,"percentChange":-3.27}},{"tenor":"1Y","targetExpiry":1822071900082,"availability":"unavailable","unavailableReason":"The target tenor falls outside the listed-expiry range at one or both snapshots; extrapolated values are suppressed.","atmIv":{"current":null,"previous":null,"change":null,"percentChange":null},"rr25":{"current":null,"previous":null,"change":null,"percentChange":null},"bf25":{"current":null,"previous":null,"change":null,"percentChange":null}}],"realisedVolatility":{"source":"canonical/BTC-USD-INDEX (DERIBIT and OKX indexes)","fallbackObservations":72,"fallbackPolicy":"Missing canonical minutes use the stored Deribit index first, then the stored OKX index; canonical bars always take precedence.","samplingInterval":"1 minute","annualizationBasis":"365 days","windowEnd":"2026-09-27T19:05:00+00:00","spotWindowStart":"2026-09-26T19:05:00+00:00","spotMetric":"spot-index return","spotUnit":"percent","spotMove24hPercent":0.84,"rv24hPercent":18.32,"rv7dPercent":35.95,"rv30dPercent":34.45,"observations":{"24h":1440,"7d":10080,"30d":43200},"coverage":{"24h":{"status":"complete","observedReturns":1440,"expectedReturns":1440,"coveragePercent":100,"missingPriceMinutes":0,"missingIntervals":0,"largestMissingRunMinutes":0,"unavailableReason":null},"7d":{"status":"complete","observedReturns":10080,"expectedReturns":10080,"coveragePercent":100,"missingPriceMinutes":0,"missingIntervals":0,"largestMissingRunMinutes":0,"unavailableReason":null},"30d":{"status":"complete","observedReturns":43200,"expectedReturns":43200,"coveragePercent":100,"missingPriceMinutes":0,"missingIntervals":0,"largestMissingRunMinutes":0,"unavailableReason":null}},"coveragePolicy":{"version":"observed-minute-returns-v1","minimumCoveragePercent":null,"minimumCoveragePercentByWindow":{"24h":98,"7d":97,"30d":99.5},"maximumMissingRunMinutes":60,"methodology":"Each RV window qualifies independently. RV annualises the mean squared observed one-minute log return; returns spanning gaps are excluded, not interpolated or zero-filled. Partial estimates assume observed minutes are representative and may miss volatility during gaps."},"spotUnavailableReason":null,"oneWeekAtmIvPercent":32.76,"oneWeekIvMinus7dRvPoints":-3.19,"oneWeekIvMinus24hRvPoints":14.44,"oneWeekIvMinus30dRvPoints":-1.69,"oneWeekIvTo7dRvRatio":null,"spreadPercentile":null},"realisedVolatilityUnavailableReason":null}