{"schemaVersion":1,"asset":"BTC","reportDate":"2026-06-18","timestamps":{"currentSnapshotAt":"2026-06-18T23:59:00+00:00","previousSnapshotAt":"2026-06-17T23:59:00+00:00","generatedAt":"2026-07-25T18:42:37+00:00"},"comparison":{"status":"available","note":null},"provenance":{"reportArtifact":"published daily report","sourceReport":"BTC","sourceReportHref":"/reports/2026-06-18","source":"Derivasys proprietary historical SVI surface database","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 interpolated independently at 1W, 2W, 1M, 3M, 6M, 9M and 1Y; headline rankings prioritise 1W, 2W, 1M, 3M, 6M and 1Y.","realisedVolatility":null},"tenors":[{"tenor":"1W","targetExpiry":1782431944548,"availability":"available","unavailableReason":null,"atmIv":{"current":39.52,"previous":36.08,"change":3.44,"percentChange":9.53},"rr25":{"current":-9.07,"previous":-5.26,"change":-3.81,"percentChange":-72.43},"bf25":{"current":3.83,"previous":2.66,"change":1.17,"percentChange":43.98}},{"tenor":"2W","targetExpiry":1783036744548,"availability":"available","unavailableReason":null,"atmIv":{"current":39.83,"previous":36.91,"change":2.92,"percentChange":7.91},"rr25":{"current":-9.07,"previous":-6.47,"change":-2.6,"percentChange":-40.19},"bf25":{"current":3.15,"previous":2.57,"change":0.58,"percentChange":22.57}},{"tenor":"1M","targetExpiry":1784419144548,"availability":"available","unavailableReason":null,"atmIv":{"current":39.22,"previous":37.14,"change":2.08,"percentChange":5.6},"rr25":{"current":-8.02,"previous":-6.44,"change":-1.58,"percentChange":-24.53},"bf25":{"current":2.94,"previous":2.4,"change":0.54,"percentChange":22.5}},{"tenor":"3M","targetExpiry":1789689544548,"availability":"available","unavailableReason":null,"atmIv":{"current":39.76,"previous":38.42,"change":1.34,"percentChange":3.49},"rr25":{"current":-6.71,"previous":-5.83,"change":-0.88,"percentChange":-15.09},"bf25":{"current":2.75,"previous":2.55,"change":0.2,"percentChange":7.84}},{"tenor":"6M","targetExpiry":1797551944548,"availability":"available","unavailableReason":null,"atmIv":{"current":42.21,"previous":41.48,"change":0.73,"percentChange":1.76},"rr25":{"current":-5.21,"previous":-4.97,"change":-0.24,"percentChange":-4.83},"bf25":{"current":2.87,"previous":2.85,"change":0.02,"percentChange":0.7}},{"tenor":"9M","targetExpiry":1805414344548,"availability":"available","unavailableReason":null,"atmIv":{"current":43.14,"previous":42.56,"change":0.58,"percentChange":1.36},"rr25":{"current":-4.4,"previous":-4.36,"change":-0.04,"percentChange":-0.92},"bf25":{"current":3,"previous":2.94,"change":0.06,"percentChange":2.04}},{"tenor":"1Y","targetExpiry":1813363144548,"availability":"available","unavailableReason":null,"atmIv":{"current":43.61,"previous":43.09,"change":0.52,"percentChange":1.21},"rr25":{"current":-3.99,"previous":-4.05,"change":0.06,"percentChange":1.48},"bf25":{"current":3.05,"previous":2.99,"change":0.06,"percentChange":2.01}}],"realisedVolatility":null,"realisedVolatilityUnavailableReason":null}