{
  "symbol": "USDCHF",
  "display": "USDCHF",
  "asset_class": "forex",
  "timeframe": "H1",
  "rows": 7718,
  "start": "2024.09.27 05:00:00",
  "end": "2025.12.24 21:00:00",
  "score": 80.0,
  "grade": "C",
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  "warning_count": 3,
  "checks": {
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    "out_of_order": 0,
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    "zero_volume_pct": 100.0,
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    "zero_spread_pct": 100.0,
    "negative_spread": 0,
    "extreme_returns": 0,
    "gaps": 1,
    "largest_gap_seconds": 10500,
    "largest_gap_start": "2024.12.08 23:05:00",
    "weekend_bars": 0
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  "issues": [
    {
      "severity": "warning",
      "check": "gaps",
      "count": 1,
      "message": "Gap greater than 2x timeframe and under 24h"
    },
    {
      "severity": "warning",
      "check": "zero_volume",
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      "message": "Zero or missing tick volume"
    },
    {
      "severity": "warning",
      "check": "zero_spread",
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      "message": "Zero or missing spread"
    }
  ],
  "generated_at": "2026-11-01",
  "report_url": "/historical-data/data-quality/detail.php?symbol=USDCHF&tf=H1"
}