{"schemaVersion":1,"asset":"BTC","reportDate":"2026-09-25","timestamps":{"currentSnapshotAt":"2026-09-25T17:28:00+00:00","previousSnapshotAt":"2026-09-24T17:28:00+00:00","generatedAt":"2026-09-25T17:28:43+00:00"},"comparison":{"status":"available","note":null},"provenance":{"reportArtifact":"published daily report","sourceReport":"BTC","sourceReportHref":"/reports/2026-09-25","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":1790962080450,"availability":"available","unavailableReason":null,"atmIv":{"current":29.94,"previous":32.5,"change":-2.56,"percentChange":-7.88},"rr25":{"current":-0.91,"previous":-2.15,"change":1.24,"percentChange":57.67},"bf25":{"current":1.65,"previous":1.99,"change":-0.34,"percentChange":-17.09}},{"tenor":"2W","targetExpiry":1791566880450,"availability":"available","unavailableReason":null,"atmIv":{"current":31.93,"previous":33.47,"change":-1.54,"percentChange":-4.6},"rr25":{"current":-1,"previous":-1.72,"change":0.72,"percentChange":41.86},"bf25":{"current":1.64,"previous":1.82,"change":-0.18,"percentChange":-9.89}},{"tenor":"1M","targetExpiry":1792949280450,"availability":"available","unavailableReason":null,"atmIv":{"current":33.76,"previous":34.72,"change":-0.96,"percentChange":-2.76},"rr25":{"current":-0.79,"previous":-1.31,"change":0.52,"percentChange":39.69},"bf25":{"current":1.71,"previous":1.75,"change":-0.04,"percentChange":-2.29}},{"tenor":"3M","targetExpiry":1798219680450,"availability":"available","unavailableReason":null,"atmIv":{"current":37.23,"previous":37.63,"change":-0.4,"percentChange":-1.06},"rr25":{"current":-0.62,"previous":-0.8,"change":0.18,"percentChange":22.5},"bf25":{"current":2.02,"previous":2.04,"change":-0.02,"percentChange":-0.98}},{"tenor":"6M","targetExpiry":1806082080450,"availability":"available","unavailableReason":null,"atmIv":{"current":38.13,"previous":38.58,"change":-0.45,"percentChange":-1.17},"rr25":{"current":-0.21,"previous":-0.21,"change":0,"percentChange":0},"bf25":{"current":2.27,"previous":2.25,"change":0.02,"percentChange":0.89}},{"tenor":"9M","targetExpiry":1813944480450,"availability":"available","unavailableReason":null,"atmIv":{"current":38.86,"previous":39.22,"change":-0.36,"percentChange":-0.92},"rr25":{"current":0.05,"previous":-0.11,"change":0.16,"percentChange":145.45},"bf25":{"current":2.43,"previous":2.29,"change":0.14,"percentChange":6.11}},{"tenor":"1Y","targetExpiry":1821893280450,"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":"2026-09-25T17:28:00+00:00","spotWindowStart":"2026-09-24T17:28:00+00:00","spotMetric":"spot-index return","spotUnit":"percent","spotMove24hPercent":-0.56,"rv24hPercent":null,"rv7dPercent":null,"rv30dPercent":null,"observations":{"24h":1370,"7d":10010,"30d":43130},"coverage":{"24h":{"status":"unavailable","observedReturns":1370,"expectedReturns":1440,"coveragePercent":95.1389,"missingPriceMinutes":68,"missingIntervals":2,"largestMissingRunMinutes":67,"unavailableReason":"24h RV requires at least 98% valid one-minute returns and no price gap over 60 minutes; coverage is 95.1389% with 68 missing price minutes across 2 intervals and a largest gap of 67 minutes."},"7d":{"status":"unavailable","observedReturns":10010,"expectedReturns":10080,"coveragePercent":99.3056,"missingPriceMinutes":68,"missingIntervals":2,"largestMissingRunMinutes":67,"unavailableReason":"7d RV requires at least 97% valid one-minute returns and no price gap over 60 minutes; coverage is 99.3056% with 68 missing price minutes across 2 intervals and a largest gap of 67 minutes."},"30d":{"status":"unavailable","observedReturns":43130,"expectedReturns":43200,"coveragePercent":99.838,"missingPriceMinutes":68,"missingIntervals":2,"largestMissingRunMinutes":67,"unavailableReason":"30d RV requires at least 99.5% valid one-minute returns and no price gap over 60 minutes; coverage is 99.8380% with 68 missing price minutes across 2 intervals and a largest gap of 67 minutes."}},"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":29.94,"oneWeekIvMinus7dRvPoints":null,"oneWeekIvMinus24hRvPoints":null,"oneWeekIvMinus30dRvPoints":null,"oneWeekIvTo7dRvRatio":null,"spreadPercentile":null},"realisedVolatilityUnavailableReason":null}