{
  "function": "YEARFRAC",
  "software": "Gnumeric",
  "guide": "/gnumeric/functions/yearfrac/",
  "review_date": "2026-10-12",
  "scope": "Selected example checks, not certification of every formula, error, locale or cross-application import/export.",
  "native_engine": null,
  "native_assertions": 0,
  "native_observations": 0,
  "native_cases": [],
  "independent_model_cases": [
    {
      "software": "gnumeric",
      "function": "YEARFRAC",
      "case": "basis 0",
      "formula": "",
      "actual": 0.5,
      "expected": 0.5,
      "passed": true,
      "method": "Documented day-count convention model on unambiguous endpoints",
      "native_application": false
    },
    {
      "software": "gnumeric",
      "function": "YEARFRAC",
      "case": "basis 2",
      "formula": "",
      "actual": 0.5055555555555555,
      "expected": 0.505555556,
      "passed": true,
      "method": "Documented day-count convention model on unambiguous endpoints",
      "native_application": false
    },
    {
      "software": "gnumeric",
      "function": "YEARFRAC",
      "case": "basis 3",
      "formula": "",
      "actual": 0.4986301369863014,
      "expected": 0.498630137,
      "passed": true,
      "method": "Documented day-count convention model on unambiguous endpoints",
      "native_application": false
    },
    {
      "software": "gnumeric",
      "function": "YEARFRAC",
      "case": "basis 4",
      "formula": "",
      "actual": 0.5,
      "expected": 0.5,
      "passed": true,
      "method": "Documented day-count convention model on unambiguous endpoints",
      "native_application": false
    },
    {
      "software": "gnumeric",
      "function": "YEARFRAC",
      "case": "prorated annual value",
      "formula": "",
      "actual": 598.3561643835617,
      "expected": 598.3561644,
      "passed": true,
      "method": "Arithmetic only; not financial advice",
      "native_application": false
    }
  ],
  "documented_expected_results_not_native": true,
  "sources": [
    "https://gnome.pages.gitlab.gnome.org/gnumeric/manual/CATEGORY_DateTime.html#gnumeric-function-YEARFRAC",
    "https://gnome.pages.gitlab.gnome.org/gnumeric-web/functions.shtml",
    "https://github.com/GNOME/gnumeric/blob/GNUMERIC_1_12_62/plugins/fn-date/functions.c",
    "https://github.com/GNOME/gnumeric/blob/GNUMERIC_1_12_62/src/gnm-datetime.h"
  ]
}