{
  "study": "The 10% a keyword search of the tariff schedule can never find",
  "measured_on": "2026-09-19",
  "schedule_snapshot": "2026-09-14",
  "source": "U.S. Customs and Border Protection, Customs Rulings Online Search System (CROSS)",
  "frame": "CROSS ny, DATE_DESC, term=a; rulings titled \"The tariff classification of...\" with exactly one code",
  "method_note": "The heading CBP assigned is located in a keyword ranking of every 4-digit heading against the ruling's merchandise description alone. Stemmed, stopworded, IDF-weighted; a heading scores as its best-matching line. No model is involved.",
  "samples": {
    "A": {
      "n": 100
    },
    "B": {
      "n": 40
    },
    "disjoint": true,
    "total": 140
  },
  "depths": [
    1,
    3,
    8,
    20,
    50,
    120
  ],
  "A": {
    "n": 100,
    "at_depth": {
      "1": {
        "n": 14,
        "pct": 14
      },
      "3": {
        "n": 32,
        "pct": 32
      },
      "8": {
        "n": 44,
        "pct": 44
      },
      "20": {
        "n": 60,
        "pct": 60
      },
      "50": {
        "n": 72,
        "pct": 72
      },
      "120": {
        "n": 83,
        "pct": 83
      }
    },
    "reachable_any_depth": {
      "n": 96,
      "pct": 96
    },
    "unreachable": {
      "n": 4,
      "pct": 4
    }
  },
  "B": {
    "n": 40,
    "at_depth": {
      "1": {
        "n": 4,
        "pct": 10
      },
      "3": {
        "n": 12,
        "pct": 30
      },
      "8": {
        "n": 18,
        "pct": 45
      },
      "20": {
        "n": 21,
        "pct": 52.5
      },
      "50": {
        "n": 26,
        "pct": 65
      },
      "120": {
        "n": 32,
        "pct": 80
      }
    },
    "reachable_any_depth": {
      "n": 36,
      "pct": 90
    },
    "unreachable": {
      "n": 4,
      "pct": 10
    }
  },
  "unreachable_examples": [
    {
      "ruling": "N363546",
      "cbp_heading": "9019",
      "cbp_heading_text": "Mechano-therapy appliances; massage apparatus; psychological aptitude-testing apparatus; ozone therapy, oxygen therapy, aerosol therapy, artificial respiration or other therapeutic respiration apparatus; parts and accessories thereof"
    },
    {
      "ruling": "N363447",
      "cbp_heading": "9505",
      "cbp_heading_text": "Festive, carnival or other entertainment articles, including magic tricks and practical joke articles; parts and accessories thereof"
    },
    {
      "ruling": "N363531",
      "cbp_heading": "9505",
      "cbp_heading_text": "Festive, carnival or other entertainment articles, including magic tricks and practical joke articles; parts and accessories thereof"
    },
    {
      "ruling": "N363777",
      "cbp_heading": "9029",
      "cbp_heading_text": "Revolution counters, production counters, taximeters, odometers, pedometers and the like; speedometers and tachometers, other than those of heading 9014 or 9015; stroboscopes; parts and accessories thereof"
    },
    {
      "ruling": "N362265",
      "cbp_heading": "8409",
      "cbp_heading_text": "Parts suitable for use solely or principally with the engines of heading 8407 or 8408"
    },
    {
      "ruling": "N362225",
      "cbp_heading": "8306",
      "cbp_heading_text": "Bells, gongs and the like, nonelectric, of base metal; statuettes and other ornaments, of base metal; photograph, picture or similar frames, of base metal; mirrors of base metal; and base metal parts thereof"
    },
    {
      "ruling": "N362451",
      "cbp_heading": "8438",
      "cbp_heading_text": "Machinery, not specified or included elsewhere in this chapter, for the industrial preparation or manufacture of food or drink, other than machinery for the extraction or preparation of animal or fixed vegetable or microbial fats or oils; parts thereof"
    },
    {
      "ruling": "N362170",
      "cbp_heading": "9505",
      "cbp_heading_text": "Festive, carnival or other entertainment articles, including magic tricks and practical joke articles; parts and accessories thereof"
    }
  ]
}