{
  "symbol": "LTCUSD",
  "display": "LTCUSD",
  "asset_class": "crypto",
  "timeframe": "H4",
  "rows": 18775,
  "start": "2018.02.09 08:00:00",
  "end": "2026.10.19 08:00:00",
  "score": 99.8,
  "grade": "A",
  "critical_count": 0,
  "warning_count": 3,
  "checks": {
    "duplicates": 0,
    "out_of_order": 0,
    "ohlc_violations": 0,
    "nonpositive_prices": 0,
    "flat_bars": 2,
    "flat_bars_pct": 0.011,
    "zero_volume": 0,
    "zero_volume_pct": 0.0,
    "zero_spread": 2,
    "zero_spread_pct": 0.011,
    "negative_spread": 0,
    "extreme_returns": 5,
    "gaps": 1,
    "largest_gap_seconds": 57600,
    "largest_gap_start": "2018.02.14 20:00:00",
    "weekend_bars": 0
  },
  "issues": [
    {
      "severity": "warning",
      "check": "gaps",
      "count": 1,
      "message": "Gap greater than 2x timeframe and under 24h"
    },
    {
      "severity": "warning",
      "check": "zero_spread",
      "count": 2,
      "message": "Zero or missing spread"
    },
    {
      "severity": "warning",
      "check": "extreme_returns",
      "count": 5,
      "message": "Extreme log return"
    },
    {
      "severity": "info",
      "check": "flat_bars",
      "count": 2,
      "message": "Open=High=Low=Close"
    }
  ],
  "generated_at": "2026-11-01",
  "report_url": "/historical-data/data-quality/detail.php?symbol=LTCUSD&tf=H4"
}