{
  "protocol": {
    "name": "CVP",
    "version": "1.0.0-proposed"
  },
  "document_status": "proposed",
  "calculator": {
    "id": "percent-change",
    "version": "1.1.0",
    "title": "Percentage Change Calculator",
    "formula_family": "percent_change",
    "capability_id": "math.percent_change",
    "verification_revision": "2026-09-08.signed-set"
  },
  "profile": "core",
  "status": "VERIFIED",
  "runner": {
    "name": "cvp-runner",
    "version": "1.0.0"
  },
  "environment": {
    "runtime": "node",
    "runtime_version": "20.19.2",
    "numeric_model": "IEEE-754 binary64",
    "os": "darwin"
  },
  "suite": {
    "id": "percent-change",
    "version": "1.1.0",
    "uri": "https://www.calculatorx.com/evidence/math.percent_change/1.1.0.json",
    "verification_revision": "2026-09-08.signed-set"
  },
  "obligation_set": [
    "CVP-PROV-01",
    "CVP-MODEL-01",
    "CVP-SCOPE-01",
    "CVP-UNIT-01",
    "CVP-REF-01",
    "CVP-GOLD-01",
    "CVP-BND-01",
    "CVP-INV-01",
    "CVP-NUM-01",
    "CVP-COV-01",
    "CVP-CONTRACT-01",
    "CVP-DEP-01",
    "CVP-ART-01",
    "CVP-PROD-01",
    "CVP-DIM-01",
    "CVP-PROP-01",
    "CVP-META-01",
    "CVP-ROUND-01",
    "CVP-XCAL-01",
    "CVP-IFACE-01"
  ],
  "provenance": {
    "mode": "direct",
    "sources": [
      {
        "label": "Math is Fun — Percentage Difference vs Percentage Error vs Percentage Change",
        "kind": "other",
        "reference": "Percentage change uses |Old| in the denominator",
        "url": "https://www.mathsisfun.com/data/percentage-difference-vs-error.html"
      },
      {
        "label": "Curran-Everett — Explorations in statistics: the analysis of change",
        "kind": "other",
        "reference": "Relative change as (final − initial) / initial",
        "url": "https://journals.physiology.org/doi/full/10.1152/advan.00018.2015"
      },
      {
        "label": "CalculatorX signed-change convention",
        "kind": "other",
        "reference": "|V₁| denominator, piecewise inverse, and multiple V₁ solutions"
      }
    ]
  },
  "controls": {
    "CVP-PROV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "Sources present on evidence"
    },
    "CVP-MODEL-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "% change = (V2−V1)/|V1|×100%"
    },
    "CVP-SCOPE-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "V1≠0; solve_for p|v1|v2; inverse V1 can be 0, 1, or 2 solutions"
    },
    "CVP-UNIT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "percent"
    },
    "CVP-REF-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "O1 model + O2 expected_values + O2 numerical_behavior"
    },
    "CVP-GOLD-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "6/6 legacy golden; 7/7 oracle-backed numeric"
    },
    "CVP-BND-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "2/2 boundary"
    },
    "CVP-INV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "2 Evidence illegal-input + 2/2 oracle-backed error-code (exact_error_match, not ULP)"
    },
    "CVP-NUM-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "max_error_observed_ulp=0; policy declared a priori"
    },
    "CVP-COV-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "5/5 declared partitions (forward, inverse-v2, inverse-v1, invalid-domain, xcal) · 6 golden / 2 boundary unique cases · 2 Evidence invalid-input (may overlap boundary)"
    },
    "CVP-CONTRACT-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "1/1 contract checks"
    },
    "CVP-DEP-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "engine percent-change; Node binary64"
    },
    "CVP-ART-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "release_integrity.status=verified · evidence_digest=CVP verification fingerprint v2 (canonical inputs, expected/actual/status, policy, versions; independent of generated_at) · evidence_bundle_sha256=legacy Evidence JSON bytes · production_sha256=bound production attestation report"
    },
    "CVP-PROD-01": {
      "result": "PASS",
      "applicability": "required",
      "notes": "CURRENT · site report pass · local checks pass · attestation_id=00c818a77ba026c2d6aa3f7402680cd2dac2a40a816209600bc3c3fcd0b8921c · CURRENT · Public schema 1.1.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓ · schema_const=1.1.0 · report output-const=pass · evidence-sha256=pass · semantic-contract=pass · capability-html-public-origin-agree=pass · cvp-manifest-public-origin-agree=pass · cvp-reproduce-manifest-agree=pass · calculator-html-cvp-projection=pass · evidence-html-cvp-projection=pass · attested_evidence_sha256=9424f31d3ca937ec4a453e41479201945df6495214f0a220ebb742e7fd1c3f20"
    },
    "CVP-DIM-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "relative change"
    },
    "CVP-PROP-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "5/5 property"
    },
    "CVP-META-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "1/1 metamorphic"
    },
    "CVP-ROUND-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "4/4 round-trips"
    },
    "CVP-XCAL-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "3/3 cross-calculator · xcal-pc-40-50 PASS vs math.percentage; xcal-pc-neg100-neg50 PASS vs math.percentage; xcal-pc-old0 PASS vs math.percentage; xcal-pe-na N/A (Percent error is listed as a related tool. It encodes |experimental−true|/|true|, not Δ%=100×(new−old)/|old|.); xcal-vat-na N/A (VAT is listed as a related finance tool. It does not encode the |old| percent-change identity.); xcal-compound-na N/A (Compound interest is listed as a related growth tool. It compounds over periods; it does not encode a one-step |V1| percent change.)"
    },
    "CVP-IFACE-01": {
      "result": "PASS",
      "applicability": "applicable",
      "notes": "UI (SSR) · REST · MCP equivalent (MCP uses calc API handler). ui-ssr is query-result HTML, not a live browser session."
    },
    "CVP-ORACLE-01": {
      "result": "SKIP",
      "applicability": "higher_assurance",
      "notes": "O2 present; O3 not required this wave"
    },
    "CVP-EXP-01": {
      "result": "SKIP",
      "applicability": "optional",
      "notes": "expert_reviewed=false"
    }
  },
  "interfaces": {
    "compared": [
      "ui-ssr",
      "rest",
      "mcp"
    ],
    "result": "PASS",
    "notes": "UI (SSR) · REST · MCP equivalent (MCP uses calc API handler). ui-ssr is query-result HTML, not a live browser session."
  },
  "artifacts": {
    "evidence_bundle_sha256": "419be9d36ca212e1f31369576f0af4ea65edd49d75924f7fe14d71f1f5e6bd84",
    "evidence_digest": "a7b9f7091c43c5bcbbe43d4be80b6d8bf8da4dc19f2e908b2b261cd959c5b968",
    "production_sha256": "9424f31d3ca937ec4a453e41479201945df6495214f0a220ebb742e7fd1c3f20",
    "attested_catalog_sha256": "e03ef81b30568018b171fd1fc4757c2abe9df7220d9ff35bbaf08038d7630cdb",
    "production_checks": [
      {
        "id": "math.percent_change:output-const",
        "status": "pass",
        "detail": "output const 1.1.0 vs capability 1.1.0",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      },
      {
        "id": "math.percent_change:evidence-sha256",
        "status": "pass",
        "detail": "10f1159b516c",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      },
      {
        "id": "math.percent_change:semantic-contract",
        "status": "pass",
        "detail": "8/8",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      },
      {
        "id": "math.percent_change:capability-html-public-origin-agree",
        "status": "pass",
        "detail": "public 1.1.0 vs origin 1.1.0",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      },
      {
        "id": "math.percent_change:cvp-manifest-public-origin-agree",
        "status": "pass",
        "detail": "math.percent_change/1.1.0/2026-09-08.signed-set/core/a7b9f7091c43",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z",
        "projection_compared": false,
        "observed_live_projection_at_attestation": "VERIFIED"
      },
      {
        "id": "math.percent_change:cvp-reproduce-manifest-agree",
        "status": "pass",
        "detail": "O3 reproduce not applicable",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      },
      {
        "id": "math.percent_change:calculator-html-cvp-projection",
        "status": "pass",
        "detail": "matches Manifest",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      },
      {
        "id": "math.percent_change:evidence-html-cvp-projection",
        "status": "pass",
        "detail": "matches Manifest",
        "scope": "last_attestation_snapshot",
        "current": true,
        "attestation_binding_current": true,
        "attested_at": "2026-09-10T02:52:51.379Z"
      }
    ]
  },
  "dependencies": [
    {
      "name": "percent-change-engine",
      "version": "1.1.0"
    },
    {
      "name": "percent-change-reference-oracle",
      "version": "1.0.0"
    },
    {
      "name": "math.percentage",
      "version": "1.1.1",
      "role": "cross_calculator_peer",
      "capability_id": "math.percentage",
      "evidence_digest": "e1b745d8821224141ebfee2bf2a4a250c5f4809eb79e8f583e8b1455e2cd9912",
      "evidence": "https://www.calculatorx.com/evidence/math.percentage/1.1.1.cvp.json"
    },
    {
      "name": "node",
      "version": "20.19.2"
    }
  ],
  "attestation": {
    "status": "CURRENT",
    "href": "/.well-known/calculatorx-production-attestation.json",
    "id": "00c818a77ba026c2d6aa3f7402680cd2dac2a40a816209600bc3c3fcd0b8921c",
    "attested_at": "2026-09-10T02:52:51.379Z"
  },
  "domain_review": {
    "status": "ABSENT",
    "spec_version": "1.1.0"
  },
  "timestamps": {
    "verified_at": "2026-09-10T03:41:49.442Z",
    "generated_at": "2026-09-10T03:41:49.442Z"
  },
  "tests": {
    "golden": {
      "passed": 7,
      "total": 7,
      "failed": 0
    },
    "boundary": {
      "passed": 2,
      "total": 2,
      "failed": 0
    },
    "invalid": {
      "passed": 4,
      "total": 4,
      "failed": 0,
      "comparison": "exact_error_match"
    },
    "property": {
      "passed": 5,
      "total": 5,
      "failed": 0
    },
    "round_trip": {
      "passed": 4,
      "total": 4,
      "failed": 0
    },
    "metamorphic": {
      "passed": 1,
      "total": 1,
      "failed": 0
    },
    "contract": {
      "passed": 1,
      "total": 1,
      "failed": 0
    },
    "cross_interface": {
      "passed": 1,
      "total": 1,
      "failed": 0
    },
    "cross_calculator": {
      "passed": 3,
      "total": 3,
      "failed": 0
    }
  },
  "numerical": {
    "representation": "IEEE-754 binary64 signed percent change",
    "tolerance": {
      "type": "ulp",
      "value": 2,
      "rationale": "Independent (V₂−V₁)/|V₁|×100 vs IUT; ≤2 ULP on value and each inverse candidate. Declared a priori.",
      "declared_before_evaluation": true
    },
    "max_error_observed": 0
  },
  "coverage": {
    "partitions": [
      {
        "id": "forward",
        "description": "Forward % change from V1, V2",
        "exercised": true,
        "case_count": 16
      },
      {
        "id": "inverse-v2",
        "description": "Solve final V2",
        "exercised": true,
        "case_count": 3
      },
      {
        "id": "inverse-v1",
        "description": "Solve initial V1",
        "exercised": true,
        "case_count": 7
      },
      {
        "id": "invalid-domain",
        "description": "Invalid inputs",
        "exercised": true,
        "case_count": 4
      },
      {
        "id": "xcal",
        "description": "Cross-calculator |old| identity vs Percentage Change mode; Percent error / VAT / Compound interest N/A",
        "exercised": true,
        "case_count": 3
      }
    ]
  },
  "reference": {
    "items": [
      {
        "class": "O1",
        "reference_scope": "model",
        "scope": "model",
        "label": "Signed percent change with |V1| denominator"
      },
      {
        "class": "O2",
        "reference_scope": "expected_values",
        "scope": "expected_values",
        "label": "Separate-module percent-change oracle (signed branches + full inverse set)",
        "engine": {
          "name": "percent-change-reference",
          "precision_bits": 53,
          "independent_of_iut": true,
          "same_runtime_as_iut": true
        }
      },
      {
        "class": "O2",
        "reference_scope": "numerical_behavior",
        "scope": "numerical_behavior",
        "label": "Same O2 module backs ≤2 ULP value and candidate-set comparison vs IUT",
        "engine": {
          "name": "percent-change-reference",
          "precision_bits": 53,
          "independent_of_iut": true,
          "same_runtime_as_iut": true
        }
      }
    ]
  },
  "links": {
    "legacy_evidence": "https://www.calculatorx.com/evidence/math.percent_change/1.1.0.json",
    "evidence_page": "https://www.calculatorx.com/evidence/math.percent_change/1.1.0",
    "calculator": "https://www.calculatorx.com/calc/math/percentage-change",
    "schema": "https://www.calculatorx.com/developers/cvp/schema/cvp-evidence-1.0.json",
    "protocol": "https://www.calculatorx.com/developers/cvp/spec/1.0",
    "manifest": "https://www.calculatorx.com/evidence/math.percent_change/1.1.0.cvp.json",
    "manifest_immutable": "https://www.calculatorx.com/evidence/math.percent_change/1.1.0/2026-09-08.signed-set.cvp.json",
    "reproduce": "https://www.calculatorx.com/evidence/math.percent_change/reproduce"
  },
  "disclosure": {
    "policy": "calculatorx-public-evidence-v1",
    "full_validation": "private",
    "representation": "summary"
  }
}