{
  "schema_version": 1,
  "retrieved_at": "2026-08-20",
  "provider": "National Institute of Standards and Technology",
  "documentation_url": "https://physics.nist.gov/cuu/Constants/",
  "editions": {
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      "url": "https://physics.nist.gov/cuu/Constants/ArchiveASCII/allascii_1998.txt",
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      "sha256": "847bee08b633b1f37be41c1c26bf7ddafc40b8d52e300515d49656d339c9523a"
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      "path": "raw/allascii_2002.txt",
      "bytes": 31183,
      "sha256": "9e80262e7f665d5649078e63713d316397b0e0674ba794d7a318230978a62dda"
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    "2006": {
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      "path": "raw/allascii_2006.txt",
      "bytes": 32861,
      "sha256": "4bd54de1b198718b9144a2d5de69b2f112a0ae2ff1dbdba15b349809df53ccf3"
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    "2010": {
      "url": "https://physics.nist.gov/cuu/Constants/ArchiveASCII/allascii_2010.txt",
      "path": "raw/allascii_2010.txt",
      "bytes": 38878,
      "sha256": "6c9eeedca8693cd2ed772d017c7bb07ba3436cc38143c45f6aa6c0afc0ccebb2"
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    "2014": {
      "url": "https://physics.nist.gov/cuu/Constants/ArchiveASCII/allascii_2014.txt",
      "path": "raw/allascii_2014.txt",
      "bytes": 38532,
      "sha256": "c0c95610c9e6f01ffe57cc2e64ebc43ccf4958507ca4e83f0d1bf56843d739e0"
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    "2018": {
      "url": "https://physics.nist.gov/cuu/Constants/ArchiveASCII/allascii_2018.txt",
      "path": "raw/allascii_2018.txt",
      "bytes": 40689,
      "sha256": "8c47c05db62c4d314a5244db51a47b4831616e55a8d357ced373a8620ff43be1"
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  "source_note": "NIST CODATA complete-listing ASCII tables. The 2022 edition is the current NIST table; earlier editions use archived NIST tables."
}