> ## Documentation Index > Fetch the complete documentation index at: https://docs.amberdata.io/llms.txt > Use this file to discover all available pages before exploring further. # SVI - Historical > This endpoint provides calibrated SVI (Stochastic Volatility Inspired) parameters for BTC and ETH options traded on Deribit, with hourly granularity. The data covers each hour from April 1, 2019, to the present, offering a historical view of volatility surface calibrations for these assets. Download the SVI White Paper here: https://go.amberdata.io/hubfs/SVITrueLineWhitepaper.pdf ## OpenAPI ````yaml get /analytics/volatility/svi-hourly openapi: 3.1.0 info: title: derivatives-api version: '2' servers: - url: https://api.amberdata.com/markets/derivatives security: - sec0: [] paths: /analytics/volatility/svi-hourly: get: summary: SVI - Historical description: > This endpoint provides calibrated SVI (Stochastic Volatility Inspired) parameters for BTC and ETH options traded on Deribit, with hourly granularity. The data covers each hour from April 1, 2019, to the present, offering a historical view of volatility surface calibrations for these assets. Download the SVI White Paper here: https://go.amberdata.io/hubfs/SVITrueLineWhitepaper.pdf operationId: derivatives-svi-historical parameters: - name: exchange in: query description: | **[Required]** The exchange for which SVI calibration occurs. **[Examples]** ` deribit ` required: true schema: type: string default: deribit - name: currency in: query description: > **[Required]** The underlying currency for which there are listed option instruments. **[Examples]** ` BTC | ETH ` required: true schema: type: string default: BTC - name: startDate in: query description: >- **[Options]** This parameter sets the starting date of historical data to be pulled. schema: type: string format: date-time default: '2024-10-03T00:00:00.000Z' - name: endDate in: query description: >- **[Options]** This parameter sets the ending date of historical data to be pulled. schema: type: string format: date-time default: '2024-10-04T00:00:00.000Z' - name: timeInterval in: query description: > **[Optional]** Time interval of data frequency for the selected date range. **[Examples]** hour | day` schema: type: string default: hour - name: sviFormat in: query description: >- **[Optional]** This parameter can be either blank (default) or "TAU" which returns the SVI parameters and days to expiration as a decimal to years. schema: type: string - name: timeFormat in: query description: > **[Optional]** Time format of the timestamps in the return payload. **[Defaults]** `milliseconds | ms* | iso | iso8601 | hr | human_readable` schema: type: string default: hr responses: '200': description: '200' content: application/json: examples: Result: value: status: 200 title: OK description: Successful request payload: data: - currency: BTC daysToExpiration: 0.981726 expirationTimestamp: '2024-10-04' forwardDifference: 23.761719 indexPrice: 60633.29 sviA: -0.0036135927428977404 sviB: 0.03935472975957192 sviM: 0.049948912 sviRho: 0.28880113 sviSigma: 0.11719716 timestamp: 2024-10-03 00:00:00 000 - currency: BTC daysToExpiration: 7.981726 expirationTimestamp: '2024-11-08' forwardDifference: 443.0625 indexPrice: 60633.29 sviA: -0.04308736417038395 sviB: 0.1421164341760755 sviM: -0.14133328 sviRho: -0.28546438 sviSigma: 0.5484994 timestamp: 2024-10-03 00:00:00 000 - currency: BTC daysToExpiration: 48.981726 expirationTimestamp: '2024-11-29' forwardDifference: 715.03125 indexPrice: 60633.29 sviA: -0.012232022257476834 sviB: 0.15892159610618226 sviM: -0.27807012 sviRho: -0.488882 sviSigma: 0.44427034 timestamp: 2024-10-03 00:00:00 000 - currency: BTC daysToExpiration: 87.981726 expirationTimestamp: '2024-12-27' forwardDifference: 1088.4492 indexPrice: 60633.29 sviA: -0.4301923736169705 sviB: 0.363443476918354 sviM: -0.52641076 sviRho: -0.3564624 sviSigma: 1.4864652 timestamp: 2024-10-03 00:00:00 000 - currency: BTC daysToExpiration: 197.981726 expirationTimestamp: '2025-03-28' forwardDifference: 2243.4102 indexPrice: 60633.29 sviA: -2.6838196813543718 sviB: 1.43548647335823 sviM: -2.571555 sviRho: -0.6810587 sviSigma: 2.7066078 timestamp: 2024-10-03 00:00:00 000 - currency: BTC daysToExpiration: 267.981726 expirationTimestamp: '2025-06-27' forwardDifference: 3603.3594 indexPrice: 60633.29 sviA: -0.5035042204544481 sviB: 0.39831238488045967 sviM: -0.19830601 sviRho: -0.07523702 sviSigma: 1.9166467 timestamp: 2024-10-03 00:00:00 000 - currency: BTC daysToExpiration: 357.981726 expirationTimestamp: '2025-09-26' forwardDifference: 5230.3594 indexPrice: 60633.29 sviA: 0.16905168861103947 sviB: 0.2443234348610282 sviM: -0.6533904 sviRho: -0.4180356 sviSigma: 0.82554317 timestamp: 2024-10-03 00:00:00 000 metadata: api-version: '2023-09-30' schema: type: object properties: status: type: integer example: 200 default: 0 title: type: string example: OK description: type: string example: Successful request payload: type: object properties: data: type: array items: type: object properties: currency: type: string example: BTC daysToExpiration: type: number example: 0.0036438357 default: 0 expirationTimestamp: type: string example: '2024-10-04' forwardDifference: type: number example: 23.761719 default: 0 indexPrice: type: number example: 60633.29 default: 0 sviA: type: number example: -0.0036135927428977404 default: 0 sviB: type: number example: 0.03935472975957192 default: 0 sviM: type: number example: 0.049948912 default: 0 sviRho: type: number example: 0.28880113 default: 0 sviSigma: type: number example: 0.11719716 default: 0 timestamp: type: string example: 2024-10-03 00:00:00 000 metadata: type: object properties: api-version: type: string example: '2023-09-30' '400': description: '400' content: application/json: examples: Result: value: {} schema: type: object properties: {} deprecated: false security: - ApiKeyAuth: [] components: securitySchemes: ApiKeyAuth: type: apiKey in: header name: x-api-key ````